Spence, Nicol C.W.
Wilhelm Fink Verlag , 1976
Buku Teks
Langacker, Ronald W., author
Harcourt, Brace & World, 1968
Buku Teks
Lyons, John, author
Cambridge University Press, 1991
Buku Teks
Routledge , 1992
Buku Teks
Brown, Penelope, author
Cambridge University Press , 1987
Buku Teks