edited by Carroll W. Pursell
MIT Press, 1981
Buku Teks SO
edited by Don Nix and Rand Spiro
Lawrence Erlbaum Associates, 1990
Buku Teks
Daniels, Klaus
Birkhauser, 1987
Buku Teks SO
Englert, Robert D.
McGraw-Hill, 1990
Buku Teks SO
Ria Utami
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2014
UI - Skripsi Membership