edited by Donald H. Shively
Princeton University Press, 1971
Buku Teks
edited Carmen Blacker [and others]
Princeton University Press, 1971
Buku Teks
Portune, Robert
The W.H. Anderson Company, 1971
Buku Teks
Artikel Jurnal
International Society for Educational Information
ISEI, 1987
Buku Teks