1. J. P. Das is a professor of educational psychology at the University of Alberta, Canada. He received his PhD in psychology from the University of London.
2. Gay Bisanz is an assistant professor of psychology at the University of Alberta. She received her PhD in psychology from the University of Pittsburgh.
3. Gabriel Mancini received her PhD in educational psychology from the University of Alberta. Address: Dr. J. P. Das, Centre for the Study of Mental Retardation, 6–123D Education North. University of Alberta, Edmonton, Alberta, Canada T6G 2G5.