APA
(1981). Sputter;s guide to sea & fresh water birds. London: Usborne Publishing.
Chicago
1981. Sputter;s guide to sea & fresh water birds. London: Usborne Publishing.
Harvard
(1981). Sputter;s guide to sea & fresh water birds. London: Usborne Publishing.
MLA
Sputter;s guide to sea & fresh water birds. London: Usborne Publishing. 1981.