O`Brien, James A., 1936-, author
McGraw-Hill, 2003
Buku Teks
Baliio, Tino, author
Macmillan Library reference USA, 1993
Buku Referensi
Keith, Lyman A., author
McGraw-Hill, 1975
Buku Teks
Coppock, Joseph D., author
McGraw-Hill, 1959
Buku Teks
Chua, Christian, author
Routledge, 2008
Buku Teks