Himus, Godfrey W., author
Harmondsworth, Middlesex, 1954
Buku Referensi
Los Angeles : John C. Winston, 1942
Buku Referensi
Hartmann, Reinhard R.K., author
Routledge, 1998
Buku Referensi
editor, Ruth D. Whitehouse
Macmillan Press, 1983
Buku Referensi
editor Ruth D. Whitehouse
Facts On File Publications, 1983
Buku Referensi