Sawhill, John C.
Harper's Magazine, 1979
Buku Teks
Kynghee University Press, 1975
Buku Teks
[ISOS, University of Kassel, Universitas Indonesia], 2010
UI - Makalah dan Kertas Kerja
University of Queensland Press, 1972
Buku Teks
Robertson, Ben
University of queensland press, 2010
Buku Referensi