Ratna Sufiatin
Fakultas Ilmu Pengetahuan Budaya Universitas Indonesia, 1999
UI - Tesis Membership
Lyon, John K.
John Wiley & Sons, 1971
Buku Teks SO
Tsichritzis, Dionysios C.
Academic Press, 1977
Buku Teks SO
Cardenas, Alfonso F.
Allyn and Bacon, 1979
Buku Teks SO
Curtice, Robert M.
Van Nostrand Reinhold, 1982
Buku Teks SO