Cannon, Michael, author
Viking O`Neil, 1983
Buku Teks
Norden, Mary, author
Conran Octopus Limited, 2000
Buku Referensi
Idea Books, 1997
Buku Referensi
Wharton, Edith, author
Random House, 1994
Buku Teks
Seward, Linda, author
Reed Consumer Books, 1992
Buku Referensi