Hudson, Alastair, author
Cavendish Publishing Limited, 2003
Buku Teks
Adams, Francis V., author
McGraw-Hill, 2007
Buku Teks
compiled and edited by Samuel E. Krug
Metritech, 1993
Buku Referensi
Sydenham, Angela, author
Sweet & Maxwell, 2000
Buku Teks
Gunton, George
Appelton and Company , 1899
Buku Teks