Loveday, George, author
Longman, 1995
Buku Teks
compiled and edited by L. L. Farkas
McGraw-Hill, 1966
Buku Teks
Metzger, Daniel L., author
Prentice-Hall, 1981
Buku Teks
Kasap, S.O, author
McGraw-Hill, 2006
Buku Teks
Villanucci, Robert S., author
Prentice-Hall, 1981
Buku Teks