Garden City Books, [date of publication not identified]
Buku Referensi
University of Technology Sydney
Lovell Johns , 1996
Buku Referensi
Hammond
Hammod Incorproted, 1986
Buku Referensi
edited by Edward B. Esphansade, Joel L. Morrison
Rand McNally & Co, 1966-1978
Buku Referensi
Heinemann Educational Books, 1986
Buku Referensi