House, C. Homer, author
Prentice-Hall, 1950
Buku Teks
Makkai, Adam
Mouton, 1972
Buku Teks
Phythian, B.A.
Hodder & Stoughton, 1980
Buku Teks
Smiith, Jeremy J., author
Routledge, 2005
Buku Teks
Parrot, Martin, author
Cambridge University Press, 2003
Buku Teks