Vermeulen, Nico
Rebo Publishers, 1994
Buku Referensi
Ody, Penelope, author
Dorling Kindersley, 1993
Buku Referensi
Walker, Richard, author
De Agostini, 1996
Buku Teks
Carroll, Stephen
Dorling Kindersley , 1992
Buku Referensi
Wingate, Peter
Penguin Books, 1972
Buku Referensi