Kelly, Robert L.,author
Wadsworth, 2010
Buku Teks SO
SPAFA, 1984
Buku Referensi
edited by Mari Pritchard Parker, Elvio Angeloni
McGraw-Hill, 2013
Buku Teks SO
illustrations by A. Kasim Abas ; text by Peter Kedit
Editions Didier Millet, 2005
Buku Referensi
Payne, Robert
Hale and Iremonger , 1911
Buku Teks SO