Martin, Anne
Routledger Kegan Paul , 1958
Buku Teks
edited by Carl Eicher and Lawrence Witt
McGraw-Hill , 1964
Buku Teks
Black, John Donald
Macmillan, 1953
Buku Teks
Cohen, R. L.
The University Press, 1955
Buku Teks
Crawford, J.G.
Stanford University Press , 1954
Buku Teks