Lang, Theodore
Ronald Press, 1944
Buku Teks
Kohler, Eric L.
Prentice-Hall, 1957
Buku Referensi
Flower, John
Accountancy Age Books, 1973
Buku Teks SO
edited by Abdel M. Agami
Random House, 1989
Buku Referensi
Vance, Lawrence L.
John Wiley & Sons, 1956
Buku Teks SO