Basu, Saroj Kumar
University of Calcutta India Press , 1953
Buku Teks
Australian Government Publishing Service , 1979
Buku Teks
Lewis, William Arthur, 1915-
University of Ghana by the Ghana Pub, 1971
Buku Teks
Mcdermott, Richard T.
Lexing Publishing, 2000
Buku Teks
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 1963
UI - Skripsi (Membership)