Goldschmidt, Arthur
Westview Press, 1983
Buku Teks
Ochsenwald, William
McGraw-Hill, 2011
Buku Teks
edited by Royall Brandis and Steven R. Cox
Richard D. Irwin, 1972
Buku Teks
Royal Institute of International Affairs, 1954
Buku Teks
edited by Peter Mansfield
Oxford University Press, 1973]
Buku Teks