Tutu T.W. Surowiyono
Pustaka Sinar Harapan, 1996
Buku Teks SO
Laseau, Paul
John Wiley & Sons, 2001
Buku Teks SO
Laseau, Paul
Cahners Books, 1975
Buku Teks SO
Gemmy International
Words & Visuals Press Pte Ltd, 2011
Buku Referensi
Hepler, Donald E.
McGraw-Hill, 1965
Buku Teks SO