Muhammad Asrori, author
1999
UI - Tesis (Membership)
edited by Eric Delson, Ian Tattersall, John A. Van Couvering and Alison S. Brokks
Garland Publishing, 2000
Buku Referensi
Newstrom, John W., author
McGraw-Hill, 2015
Buku Teks
Newstrom, John W., author
Tata McGraw-Hill , 1997
Buku Teks
Kohnstamm, GA, author
Anthos, 1992
Buku Referensi