Colombotos, John
Oxford University Press, 1986
Buku Teks
Fry, John, 1922-
MTP Press , 1978
Buku Teks
Spector, Rachel E., author
Appleton Century Crofts, 1985
Buku Teks
Auburn House Publ., 1982
Buku Teks
Harman, Willis, author
Berrett-Koehler , 1998
Buku Teks