Boughey, Arthur S., author
McMillan Publisher, 1975
Buku Teks
edited by Edwin D. Kilbourne, Wilson G. Smillie
MacMillan company, 1969
Buku Teks
Last, John M., 1926-, author
McGraw-Hill, 1997
Buku Teks
Richardson, W. Norman, author
Macmillan, 1976
Buku Teks
O`Neill, John, author
Routledge, 1993
Buku Teks