Lee, Maurice W., author
Richard D. Irwin, 1961
Buku Teks
Lewis, William Arthur, 1915-, author
Development, 1966
Buku Teks
Adelman, Irma, author
Stanford University Press, 1961
Buku Teks
Hamberg, Daniel, author
Harper & Row, 1971
Buku Teks
Williams, John Henry, author
Macmillan, 1951
Buku Teks