
"Handicapped People and Science" http://books.google.com/books?id=9LVFAAAAYAAJ&q=%22handicapped+people+and+science%22#search_anchor by Stephen Hawking, Science Digest 92, No. 9 (September 1984): 92 (details of citation from here http://www.enotes.com/stephen-hawking-criticism/hawking-stephen/further-reading).