Pugh, Eric, author
Oryx Press, 1981
Buku Referensi
Held, Gilbert, author
John Wiley & Sons, 1995
Buku Referensi
Rosenberg, Jerry M., author
McGraw-Hill, 1992
Buku Referensi
Ivory, Arthur E.E., author
Whitcoulls Publishers, 1982
Buku Referensi
Pence, Gregory E., author
McGraw-Hill, 2000
Buku Teks