The British Medical Association complete family health encyclopedia
edited by Tony Smith
Dorling Kindersley, 1990
 Buku Referensi
Vermeulen, Nico
The complete encyclopedia of container plants / Nico Vermeulen
Rebo , 1998
 Buku Referensi
The British medical association complete family health encyclopedia
edited by Tony Smith
Dorling Kindersley, 1995
 Buku Referensi
The New complete medical and health encyclopedia; Volume one
edited by Richard J. Wagman
J.G. Ferguson Publishing, 1992
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The New complete medical and health encyclopedia; Volume two
edited by Richard J. Wagman
J.G. Ferguson Publishing, 1992
 Buku Referensi