edited by Lee Bok Y.
McGraw-Hill, 2005
Buku Teks
edited by Carie Sussman, Barbara M. Bates-Jensen
AN Aspen , 1998
Buku Teks
editor, Hannu Larjava
John Wiley & Sons, 2012
Buku Teks
Muhlbauer, W. Kent., author
Gulf Publishing Company, 1992
Buku Referensi
UNDP and ESCAP , 1987
Buku Teks