Llewellyn, Kate
Globe Press, 1990
Buku Teks
Roberts, Ainslie
Rigby Limited, 1971
Buku Teks
Wannan, Bill, compiler
Viking O'Neil, Penguin Books Australia, 1987
Buku Referensi
House, William J.
International Labour Office, 1985
Buku Teks
edited by George Mackaness
Horwitz-Grahame, 1965
Buku Teks