Sanim, Bunasor
Bogor : IPB, 2003,
Buku Teks
Artikel Jurnal
Cynthia Kania, author
Universitas Indonesia, 2003
UI - Tesis Membership
Batubara, Marwan, author
[publisher not identified], 2009
Buku Teks
Thurow, Lester C., author
Wadsworth, 1970
Buku Teks