Heller, Richard F., author
Oxford University Press, 2006
Buku Teks
Rodgers, Gerry
International Labor Office , 1984
Buku Teks
Glicken, Morley D., author
Elsevier , 2009
Buku Teks
Deborah R. McFarlane, editor
Jones & Bartlett Learning, 2015
Buku Teks
El-Sayed, Abdulrahman M., author
Oxford University Press, 2017
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