Ehrlich, Eugene, author
McGraw-Hill , 2011
Buku Teks
Jesus Romero-Trillo, editor
Springer, 2012
eBooks
Makkink, H.J., author
Nijgh and Van Ditmar, 1951
Buku Teks
Foreword by Wong Lian Aik
Center for English Language Communication. NUS, 2001
Buku Teks
Henderson, Harold Gould, author
George Allen and Unwin, 1945
Buku Teks