Wells, Lisa K., author
Prentice-Hall, 1995
Buku Teks
Catholic Press, 1953
Buku Referensi
Apte, Vaman Shivram, author
Motilal Banarsidass, 1959
Buku Referensi
Huddleston, Rodney, author
Cambridge University Press, 2006
Buku Teks
Barnett, E. de Barry, author
Longman, 1957
Buku Teks