Baumol, William J., author
Harper & Brother Publisher, 1954
Buku Teks
Kiekhofer, William H., author
D. Appleton Century, 1946
Buku Teks
edited by Arthur L. Grey and John E. Elliot
Houghton Mifflin, 1965
Buku Teks
Sukma Widyanti, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2013
UI - Tesis (Membership)
Artikel Jurnal