Puchta, Herbert
Cambridge University Press, 2012
Buku Teks
McGraw-Hill, 1964
Buku Teks
Honey, William Bowyer, 1889-, author
George Routledge & Sons, 1947
Buku Teks
Harrison, G.B., author
Penguin Books , 1953
Buku Teks
Burrow, J.A., author
BlackWell Publishing, 2004
Buku Teks