International Labour Office, 1994
Buku Teks
Codline, Sylvia
Gulf Publishing Company, 1992
Buku Teks
A. F. Al-Assaf
World Health Organization, 2001
Buku Teks
Jorg Mahlich, Werner Pascha, editors
[Springer-Verlag, ], 2012
eBooks
edited by Jerri Killian; Niklas Eklund
CRC Press, 2008
Buku Teks