Please note that our site uses cookies to provide basic functionality and feedback.
By continuing to use our site you accept this use. More information is provided in our privacy page.
Don't show me this again.
Due to the current COVID-19 situation, our customers may experience some delivery delays. We apologise for any inconvenience this may cause.
Click here to purchase the two volumes of Simplified Signs: A Manual Sign-Communication System for Special Populations at a discounted rate.
Parents and teachers of children with special communication needs -- these books are for you. 'Simplified Signs' can be the first step toward meaningful communication.
Jean Frances Andrews, emeritus Professor, Lamar University, Department of Deaf Studies/Deaf Education, CHOICE Connects, May 2021 Vol. 58 No. 9
Simplified Signs presents a system of manual sign communication intended for special populations who have had limited success mastering spoken or full sign languages. It is the culmination of over twenty years of research and development by the authors. The Simplified Sign System has been developed and tested for ease of sign comprehension, memorization, and formation by limiting the complexity of the motor skills required to form each sign, and by ensuring that each sign visually resembles the meaning it conveys.
Volume 1 outlines the research underpinning and informing the project, and places the Simplified Sign System in a wider context of sign usage, historically and by different populations. Volume 2 presents the lexicon of signs, totalling approximately 1000 signs, each with a clear illustration and a written description of how the sign is formed, as well as a memory aid that connects the sign visually to the meaning that it conveys.
While the Simplified Sign System originally was developed to meet the needs of persons with intellectual disabilities, cerebral palsy, autism, or aphasia, it may also assist the communication needs of a wider audience – such as healthcare professionals, aid workers, military personnel , travellers or parents, and children who have not yet mastered spoken language. The system also has been shown to enhance learning for individuals studying a foreign language.
Lucid and comprehensive, this work constitutes a valuable resource that will enhance the communicative interactions of many different people, and will be of great interest to researchers and educators alike.
Visit the official website for this book at http://www.simplifiedsigns.net to access tutorials designed to help people, especially parents and teachers, learn to use the signs.
You can access a transcript of the interview with William B. Bonvillian here. You can access a transcript of the Online Book Launch of Simplified Signs: A Manual Sign-Communication System for Special Populations here.
Simplified Signs: A Manual Sign-Communication System for Special Populations, Volume 1
John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke | July 2020
650 pp. | 50 B&W illustrations | 6.14" x 9.21" (234 x 156 mm)
ISBN Paperback: 9781783749232
ISBN Hardback: 9781783749249
ISBN Digital (PDF): 9781783749256
ISBN Digital ebook (epub): 9781783749263
ISBN Digital ebook (mobi): 9781783749270
ISBN Digital (XML): 9781783749287
DOI: 10.11647/OBP.0205
BIC Subject Codes: C (Language), CB (Language: reference and general), CFZ (Sign languages, Braille and other linguistic communication); BISAC: EDU000000 (EDUCATION / General), LAN017000 (LANGUAGE ARTS & DISCIPLINES / SignLanguage), LAN000000 (LANGUAGE ARTS & DISCIPLINES / General); OCLC Number: 1182807790.
You may also be interested in:
Contents
Preface and Acknowledgments Download John D. Bonvillian and William Boone Bonvillian
Postscript
1. Introduction Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Addressing Concerns about Sign-Communication Training and Teaching
Special Populations
The Simplified Sign System
Goals, Clarifications, and Recommendations
Other Potential Users of the Simplified Sign System
Contents and Structure of the Two Volumes
2. Use of Manual Signs and Gestures by Hearing Persons: Historical Perspectives Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
The Origins of Language
Signs as a Natural and Universal Form of Communication
Gestural and Sign Use Cross-Culturally
Sign Communication in North America
Europeans in the New World and their Communicative Interactions through Signs
Early European Gestural Communication
Concluding Remarks
3. Deaf Persons and Sign Languages Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Deaf Education and the Recognition of Sign Languages
Sign Production
Different Sign Languages and Obstacles to Sign Communication Worldwide
Unique Aspects of Sign Languages
Iconic Signs
Sign Language Acquisition
Concluding Remarks
4. Sign Communication in Persons with an Intellectual Disability or with Cerebral Palsy Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
An Early Study
Intellectual Disability
Cerebral Palsy
Recommendations for Enhancing the Sign-Learning Environment
Selecting Signs
5. Childhood Autism and Sign Communication Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Childhood Autism
Sign-Communication Training and Teaching
Dispelling Myths
Teaching Generalization and Spontaneous Communication Skills
Motor and Imitation Abilities
Other Non-Oral Approaches
Evaluative Comments
6. Sign-Communication Intervention in Adults and Children with Aphasia Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Introduction to Aphasia and Apraxia
Sign-Communication Training Outcomes
Sign Facilitation of Spoken Language
Acquired Childhood Aphasia and Landau-Kleffner Syndrome
Developmental Language Disorder and Childhood Apraxia of Speech
Concluding Remarks
7. Use of Manual Signs and Gestures by Hearing Persons: Contemporary Perspectives Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Teaching Signs to Hearing Infants of Hearing Parents
Socioeconomic Intervention Programs and Language
Attention-Deficit Hyperactivity Disorder (ADHD) in Academic Settings
Using Manual Signs to Improve Reading Comprehension
Facilitating Foreign Language Vocabulary Acquisition
Learning to Sign May Positively Affect One’s Cognitive Abilities
Concluding Remarks
8. Development of the Simplified Sign System Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Background Information
Step One: Iconic Sign Selection
Step Two: Sign Formation Modification
Step Three: Testing of Simplified Signs with Undergraduate Students
Step Four: Comparison Testing of Simplified Signs
Step Five: Feedback from Users
Step Six: Memory Aids
Concluding Remarks
9. Application and Use of the Simplified Sign System with Persons with Disabilities Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Approaches to Teaching the Simplified Sign System
Guidelines for Using the Simplified Sign System
Frequently Asked Questions
Concluding Remarks
Appendix A: Sign Language Dictionaries and Other Sources
Appendix B: Handshapes Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Appendix C: Palm, Finger, and Knuckle Orientation Download John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke
Palm Orientation
Finger/Knuckle Orientation
Glossary
References
Author Biographies
Name Index
Subject Index
About the publishing team
John D. Bonvillian was a faculty member in the Psychology Department at the University of Virginia for thirty-seven years. He also chaired the University’s Interdepartmental Program in Linguistics. He was known for his contributions to the study of sign language, child development, psycholinguistics, and language acquisition. His research focused on typically developing children, deaf children, and children with disabilities. For the last seventeen years of his career he worked on a simplified, manual sign-communication system. The initial focus of this work was to create an easily-adopted signing system for speech-limited populations, such as individuals with autism spectrum disorder (ASD), Down syndrome, or cerebral palsy. Later, he studied applications of the Simplified Sign System for foreign language acquisition and for children in limited language environments. He and his research colleagues developed and tested a lexicon of approximately 1850 easily-formed, highly iconic signs or gestures, some of which are presented in these volumes. Bonvillian received his Ph.D. in Psychology from Stanford University, where he held a National Science Foundation doctoral fellowship. His B.A. was from Johns Hopkins University in Psychology. He authored over 100 journal articles and was an editor of the journal Sign Language Studies. Before taking his position at the University of Virginia, Bonvillian taught at Vassar College. He also served as a visiting faculty member at Gallaudet University in Washington, D.C. and the University of Canterbury in New Zealand. He died in 2018.
Tracy T. Dooley was an undergraduate honors student at the University of Virginia and a member of Dr. Bonvillian’s research group in the early 1990s, where she studied handedness in the young sign-learning children of Deaf parents. After earning B.A. degrees in Linguistics and Spanish with a minor in Psychology, she obtained her Master of Divinity degree from Emory University’s Candler School of Theology in Atlanta, GA. While studying theology, she also pursued training in sign language interpretation at DeKalb College (now Georgia State University Perimeter College). After moving back to Virginia in 2003, Ms. Dooley rejoined Dr. Bonvillian’s research group, where she focused on the expansion of the Simplified Sign System to include more concepts, the writing and editing of volumes 1 and 2, and overseeing the development of the sign illustrations. After Dr. Bonvillian’s death, Ms. Dooley updated both volumes of the system in preparation for publication.
Nicole Kissane Lee, M.D., Ed.M. had the privilege of formally starting the "Simplified Sign System” project with Dr. John Bonvillian in 1997 when she was a first-year pre-medical student at the University of Virginia. After many hours meticulously studying and testing the memory and recall of simplified signs, Dr. Lee and Dr. Bonvillian published the "Simplified Sign System” on the internet in the spring of 2001 which exponentially launched its soon-to-be international notoriety. Dr. Lee graduated from the University of Virginia in 2001 with High Distinction in Psychology under the mentorship of Dr. Bonvillian, with her thesis work on the "Simplified Sign System” gaining recognition for its unique innovation from The Today Show, CNN, The Washington Post, and CosmoGirl, to name a few. Dr. Lee went on to obtain her medical degree from the Medical College of Virginia, in Richmond, VA, her surgical residency training at the University of Florida, in Gainesville, FL, and fellowship training in advanced laparoscopic surgery at Massachusetts General Hospital in Boston, M.A. Dr. Lee continued her education while in Boston, obtaining additional fellowship training in Medical Simulation from Brigham and Women’s Hospital. She also obtained an Ed.M. with a focus in Technology and Innovation from Harvard University in 2013. Dr. Lee is currently a minimally invasive and bariatric surgeon at Indiana University. She is an Assistant Professor of Surgery and the Director of the Indiana University Surgical Skills Center. She is also Co-Director of the Indiana University Surgical Education Research Fellowship. Dr. Lee is an active member of the American College of Surgeons Accredited Education Institute (ACS/AEI) as a member of the Accreditation Review Committee, national site reviewer, and Co-Editor of the ACS/AEI Online Communities. Dr. Lee remains proud and grateful to be associated with the legendary works of her former mentor, Dr. Bonvillian. It was his enthusiasm in education and research which launched her career in medical education and related research.
Filip T. Loncke is a psycholinguist from Belgium who came to the United States in 1997 as a professor at the Curry School of Education and Human Development at the University of Virginia. Prior to his arrival in the U.S., he worked for twenty years as an educational psychologist and as a school superintendent for services for children with disabilities. He obtained his B.A. and M.A. degrees in Special Education from the University of Ghent, and an M.A. and Ph.D. degree in neurolinguistics from the University of Brussels. While in Belgium, he was a co-developer of a manual sign system that is currently still in use in parts of Europe. Since his arrival in the US in the late 1990s until Dr. Bonvillian’s passing, he collaborated with Dr. Bonvillian on several research projects related to the Simplified Sign System.
Val Nelson-Metlay was born hard-of-hearing in Chicago, IL and is now Deaf. It wasn’t until she was about twenty-five years old that she started to pick up ASL. She graduated from the University of Kansas with a B.F.A. and went on to work at several jobs: cartoonist for a small advertising agency, color separation for two greeting cards, pre-press keyliner, layout artist, and typesetter, book designer, newspaper editor and layout, and finally freelance artist. She is grateful for the opportunity to illustrate these volumes, and for the full support she has received from her family, her dear hearing friends, and many Deaf and hard-of-hearing friends.
This work is licensed under a Creative Commons Attribution 4.0 International license (CC BY 4.0). This license allows you to share, copy, distribute and transmit the text; to adapt the text and to make commercial use of the text providing attribution is made to the authors (but not in any way that suggests that they endorse you or your use of the work). Attribution should include the following information:
John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke (eds.), Simplified Signs: A Manual Sign-Communication System for Special Populations, Volume 1. Cambridge, UK: Open Book Publishers, 2020, https://doi.org/10.11647/OBP.0205
Vol. 1
1. Introduction
Chapter 1 provides an introduction to the language
and communication needs of various individuals who have difficulty
expressing themselves either through speech and/or by using one of the
full and genuine sign languages of Deaf people. The authors propose the
integration of the Simplified Sign System, a manual sign-communication
system that is comprised of iconic and easily formed signs, into the
environments of persons with various communication difficulties,
including individuals with autism, aphasia, intellectual disability, or
cerebral palsy. Various misconceptions about sign training are tackled
and countered by information highlighting the benefits of sign usage for
many different people. The authors then present the principles on
which their sign system is based, including iconicity, ease of
production, the relatively broad conceptual base of many signs, the
standardization of the signs, and the provision of a core vocabulary.
These principles also make them easier to learn and remember by other
potential users of the system, including international travellers,
parents adopting children from other countries, elderly persons who have
developed hearing impairments, foreign language instructors, and
students learning an additional spoken language.
2. Use of Manual Signs and Gestures by Hearing Persons: Historical Perspectives
Chapter 2
presents multiple accounts of the widespread use of manual signs by
hearing persons in diverse settings throughout history. From an initial
theoretical focus on the origins of language in humans, and the
potential that language first emerged from gestural or manual
communication, the reader is introduced to the views of various
historical scholars who believed that signs and gestures are a natural
means of communication and could potentially even be a universal form of
communication. Such a universal form of communication, however, meets
with a substantial obstacle in that gestures may vary widely in meaning
and usage cross-culturally. Nevertheless, such a system was developed
once before by the Indigenous peoples of North America, who spoke
hundreds of different languages. Native Americans used signs as a
lingua franca across a wide geographical area to overcome the numerous
spoken language barriers they encountered. Also covered in this chapter
are the use of signs in early contact situations and interactions
between Native Americans and Europeans, and the development of signs by
various monastic orders in Europe.
3. Deaf Persons and Sign Languages
Chapter 3 introduces the reader to various aspects
of sign languages, including their historical development and use within
educational contexts by Deaf communities in Europe and the United
States. Also covered is the initiation of the field of sign language
linguistics by William C. Stokoe, a linguist who systematically proved
that American Sign Language (ASL) was indeed a language with its own
distinct structure and properties that differed from any spoken
language. The phonological parameters of signs receive considerable
attention, highlighting ways in which the unique properties of sign
languages allow them to represent meaning in ways that are more
consistently transparent and iconic than similar phenomena in the speech
modality. Despite these similarities across sign languages, the
differences among the sign languages of the world led Deaf persons to
create and develop the lingua franca of International Sign (previously
Gestuno) for use at international conventions. Finally, the
similarities and distinctions between the processes of language
development and acquisition across the modalities of speech and sign are
discussed, as well as how signing benefits the learning of spoken
language vocabulary by hearing children.
4. Sign Communication in Persons with an Intellectual Disability or with Cerebral Palsy
In Chapter 4, the authors begin an in-depth
discussion of the use of signs with special populations, including an
early study that occurred in the West of England in the 1840s with deaf
students with intellectual disabilities. Various types of intellectual
disability are identified, including fragile X syndrome, Williams
syndrome, Down syndrome, and Angelman syndrome. The successes and
failures of speech-based and sign-based interventions are covered for
individuals with these syndromes (particularly the latter two) as well
as in persons with multiple disabilities. The authors next move on to a
discussion of the relatively sparse research related to teaching signs
to children who have cerebral palsy. Recommendations for enhancing the
sign-learning environment are provided so that all persons who use signs
as an augmentative or alternative means of communication may derive the
greatest benefit from their communicative interactions. In addition to
maximizing the positive atmosphere in which signing individuals
interact with others at school, at home, and in public, the authors
suggest that the types of signs employed may also have an impact on
whether or not signing is successful.
5. Childhood Autism and Sign Communication
Chapter 5 provides a comprehensive, historical
overview of the defining characteristics of autism spectrum disorder
(ASD) along with the various language therapies employed to improve the
communicative success of minimally verbal individuals. The various
strengths and weaknesses of such approaches are analyzed as a basis for
helping to determine which methods are likely to be the most
successful. The history of signing in persons with ASD is examined,
with a special focus on the relatively recent realization that motor
skills (both gross and fine) and imitation abilities in such individuals
may be severely impaired, thus limiting the effectiveness of sign
interventions that do not take into consideration the motor complexity
of the signs used. Since many parents and caregivers may also express
reluctance to adopt a strategy that uses signs out of fear that this
will prevent their child’s acquisition of speech, research dispelling
this myth is provided. In addition to coverage of sign-communication
interventions and strategies for promoting spontaneous communication and
generalization of sign use to multiple settings, other non-oral
approaches employed with persons with disabilities are presented as
options, including the use of real objects, the Picture Exchange
Communication System (PECS), Blissymbols, speech-generating devices, and
software applications.
6. Sign-Communication Intervention in Adults and Children with Aphasia
Chapter 6 focuses on the language and communication
impairments of adults and children that may be acquired after suffering
a head injury, stroke, brain infection, tumor, or other similar
trauma. Such persons may have had intact language abilities before the
trauma, but often present with varying degrees of severity of aphasia
that may temporarily or permanently affect their receptive understanding
of language and/or their production of language. Although most of the
literature examines such deficits in hearing persons and the resulting
impact on spoken language, deaf persons may also experience aphasic
impairments to their production and understanding of sign language. An
examination of apraxia, which often co-occurs with aphasia, provides
another dimension that needs to be analyzed when addressing strategies
for language rehabilitation. The outcomes of sign-communication
interventions in persons with aphasia are presented, along with a focus
on Amer-Ind, pantomime skills, and the use of signing to facilitate
speech. Finally, the authors address speech and language disorders such
as acquired childhood aphasia (Landau-Kleffner syndrome), developmental
language disorder (formerly known as specific language impairment) in
both hearing and deaf children, and childhood apraxia of speech.
7. Use of Manual Signs and Gestures by Hearing Persons: Contemporary Perspectives
In Chapter 7, the authors change focus from the use
of signs by deaf persons and with individuals with disabilities to how
signing may enhance the learning and processing of spoken language by
typically developing hearing children and adults. The first topic
examined is the use of signs to foster infants’ and young children’s
acquisition of their principal spoken language. Signs may further serve
as an effective intervention strategy in academic settings for children
with ADHD or as a means to improving vocabulary acquisition and reading
comprehension for children who lag behind their age group on various
language performance measures. Iconic signs and representative gestures
may also be used to facilitate the acquisition of foreign language
vocabulary when the signs are paired with the to-be-learned words.
Finally, various studies concerning the positive benefits of learning to
sign promote the possibility that using the visual-gestural modality
may confer increased skills in various cognitive domains such as spatial
memory, mental rotation, and facial discrimination.
8. Development of the Simplified Sign System
Chapter 8 provides background information on the
development of the Simplified Sign System. These steps are included so
that investigators may replicate research findings and/or develop
additional signs for their own sign-intervention programs. The authors
first discuss efforts to find highly iconic or representative gestures
in the dictionaries of various sign languages and sign systems from
around the world. If necessary, signs were then modified to make them
easier to produce based on the results of prior studies of signing
errors made by students with autism, the sign-learning children of Deaf
parents, and undergraduate students unfamiliar with any sign language.
These potential signs were then tested with different undergraduate
students to determine whether the signs were sufficiently memorable and
accurately formed. Signs that did not meet criterion were either
dropped from the system or subsequently modified and re-tested. Initial
results from comparison studies between Simplified Signs and ASL signs
and between Simplified Signs and Amer-Ind signs are presented as well.
Finally, feedback from users influenced the course of the project.
Memory aids were developed, especially for those persons who have less
familiarity with sign languages, to help explain the ties between each
sign and its referent in case that relationship is not readily or
immediately apparent to a potential learner.
9. Application and Use of the Simplified Sign System with Persons with Disabilities
In Chapter 9, various approaches to teaching signs
to non-speaking or minimally verbal persons are examined, including
general exposure, an incidental or milieu approach, games and group
activities, and specific training sessions. Learning goals are
identified not only for the main or primary user of the system, but also
for that person’s communication partners (family members, caregivers,
friends) and persons in the wider environment. Guidelines for using the
Simplified Sign System with the target populations are provided in
order to establish good and consistent communication practices that will
help to maximize users’ success with the system. Such guidelines or
strategies include ensuring a positive signing environment, establishing
visual contact, using key word signing, accepting errors in sign
formation from the main user, rewarding progress, using facial
expressions and environmental cues or contextual information to enhance
vocabulary acquisition, and adapting the rate and frequency of signing.
Finally, the authors anticipate and address many of the questions or
concerns that teachers or caregivers may have as they embark on a
program of using Simplified Signs.
Vol. 2
Preface
The Preface of Volume 2, written by the primary
author (John D. Bonvillian), offers an overview of many of the various
themes and topics covered in Volume 1. This overview is accomplished
through the historical lens of Dr. Bonvillian’s life, educational
training, and decades-long career, with a view of the corresponding
changes in the attitudes of linguists and the public toward signing and
Deaf people as various advances in sign language research were made.
Highlighted are the similarities and differences between spoken
languages and signed languages, the history of sign use in the education
of deaf students, and the introduction of signing into communication
intervention programs with non-speaking or minimally verbal children
with autism, an intellectual disability, cerebral palsy, or aphasia.
Bonvillian points out the variable outcomes of teaching signs to such
individuals before addressing possible reasons for this disparity:
delaying the introduction of signs (often because of parental fears that
signing would inhibit the development of speech skills), the lack of a
supportive signing environment, and the characteristics of the signs
themselves. He stresses the characteristics of signs that tend to be
more easily learned, remembered, and produced by non-speaking
individuals: highly iconic signs, signs with a single movement, signs
with basic or easily formed handshapes, signs that make contact with the
person’s body or non-dominant hand or arm, and signs that are highly
relevant to that individual’s life. Also mentioned are the emotional and
intellectual benefits of learning to sign, the ways signing can support
speech, and how signing may be used to teach words from a person’s
native language or to acquire a foreign or additional spoken language.
10. Introduction to the Simplified Sign System
Chapter 10 provides an introduction to the
organization of the Simplified Sign System lexicon and its supporting
materials. This chapter explains the various conventions used in the
sign illustrations so that learners can accurately interpret the
drawings, including the numbering of initial, intermediate, and final
positions; the size, shape, and repetition of arrows, quotes, and other
marks that depict the sign’s movement; and the provision of facial
expressions on signs that convey emotional information. Drawings and
expanded written descriptions of the handshapes used in the Simplified
Sign System are provided, along with information on how prevalent each
handshape is in the system and a sampling of the particular meanings
that a handshape can convey within the system. Drawings and written
descriptions of the various palm orientations and finger/knuckle
orientations used in the system are provided as well so that family
members, educators, and other professionals will be able to accurately
interpret each sign’s written description. Also discussed in this
chapter are the memory aids provided with each sign, natural variations
in sign formation and production that are to be expected, as well as
what to do if a sign learner has functional use of only one hand and
arm.
11. The Simplified Sign System Lexicon
Chapter 11 contains the first one thousand signs
of the Simplified Sign System lexicon, alphabetized by each sign’s main
gloss. Each entry in the lexicon includes a hand-drawn illustration of
how that sign is formed, a listing of any synonyms or antonyms related
to that sign, and a written description of how the sign is formed (i.e.,
the handshape(s), palm orientation(s), finger/knuckle orientation(s),
location, and movement parameters of the sign). Also provided are a
short memory aid to help learners remember the sign’s formation and a
longer memory aid that describes the visual and iconic link between how
the sign is physically formed and the meaning it conveys. Many of the
longer memory aids also include a definition of the main gloss and some
of that sign’s synonyms. If users of the system wish to look up a
particular vocabulary item, term, or idiomatic phrase, an alphabetized
Sign Index that integrates all of the main sign glosses with all of
their listed synonyms and antonyms is provided at the end of the volume.
This Sign Index directs readers to the page that contains the main sign
entry, its written description, and its memory aids.
Videos:
Watch an interview with William B. Bonvillian here.
Don't show me this again
My Basket
John D. Bonvillian, Nicole Kissane Lee, Tracy T. Dooley and Filip T. Loncke 
