1. Forensic Science Program Eberly College of ScienceThe Pennsylvania State University University Park PA USA
2. Microtrace Elgin IL USA
3. Department of Science (Professor Emeritus of Criminalistics John Jay College of Criminal Justice City University of New York New York NY USA
4. Ecole des Sciences Criminelles Police Scientifique (Professor Emeritus Université de Lausanne (UNIL Lausanne Switzerland