G & C Merriam Co., 1951
Buku Referensi
Smith, Charles John, author
Bell and Sons, 1917
Buku Referensi
Nandy, Milon, author
Composite Study Aid Publications, 1993
Buku Referensi
editor, Laurence Urdang
Macmillan Reference Books, 1995
Buku Referensi
edited by Martin H. Manser
W & R Chambers, 1995
Buku Referensi