Trainer, Timothy P, author
Thomson, 2006
Buku Teks
Congress of the U.S., Office of Technology Assessment, 1986
Buku Teks
Daza, Ricardo
Brkhauser, 2000
Buku Teks
Phillips, Christopher, author
Oxford University Press, 2016
eBooks
Johns Hopkins University Press, 1979
Buku Teks