Fishman, Betty G., author
Thomas Y. Crowell, 1969
Buku Teks
Peterson, Wallace C.
W.W. Norton & Co., 1962
Buku Teks
International Labour Office, 1964
Buku Teks
Pierre, Andrew J., author
Council on Foreign Relations, 1984
Buku Teks
edited by Marina v.N. Whitman ... [and others]
Council on Foreign Relations, 1984
Buku Teks