editor, June H.L. Wong; writers, Meng Yew Choong, Chin Mui Yoon
Star publications, 2011
Buku Referensi
Lincoln, Marshall
Amphoto, 1966
Buku Teks SO
edited by Nathan Lyons
Prentice-Hall, 1966
Buku Teks
edited by Andrew E. Hershberger
UK Wiley Blackwell,, 2014
Buku Teks SO
Langford, Michael
Focal Press, 1998
Buku Teks SO