Stanford Univ. Press ., 1961
Buku Teks
Edwards, Allen L., author
Rinehart and Winston , 1958
Buku Teks
Lewis, Edward E.
Houghton Mifflin , 1963
Buku Teks
Harman, Harry H., author
University of Chicago Press, 1968
Buku Teks
Twisk, Jos W.R., author
Cambridge University Press, 2006
Buku Teks