Altman, Nathaniel
Healing Arts Press, 2000
Buku Teks SO
Barnard, Julian
Ashgrove Press, 1988
Buku Referensi
Ursell, Amanda
A Dorling Kindersley Book, 2000
Buku Teks SO
Shealy, C. Norman
Element, 1998
Buku Referensi
Anthonio akkermans, Peter G. Drake, Bill Mattos, andy Middleton
Hermes House, 2011
Buku Referensi