Hyun-dong, Han
Alex Media Komputindo, 2012
Buku Teks SO
Lee, Ga
Elex Media Komputindo, 2013
Buku Teks SO
Oxlade, Chris
Mustard, 1999
Buku Referensi
editor in chief, Charles A. Ford
Encyclopedia Britannica Educational Corporation, 1969
Buku Referensi
Lucie Parker, editor; Laura Harger, editor
The Exploratorium and Weldon Owen Inc., 2013
Buku Referensi