Gaya APA
DR.Brill, .
(2008).
G.C.E. O Level Biology: Topic by topic
.
Singapura:
Fairfield Book Publishers.
Gaya MLA
DR.Brill, .
"G.C.E. O Level Biology: Topic by topic".
Singapura:
Fairfield Book Publishers,
2008.
Printed Book.