Jähne, Johannes, author
Edition Leipzic, 1964
Buku Teks
Oakley, Peter, author
International Labour Office, 1991
Buku Teks
Locke, Lawrence F., author
Sage, 2000
Buku Teks
Locke, Lawrence F., author
Sage, 1987
Buku Referensi
Locke, Lawrence F., author
Sage, 2014
Buku Teks