Ottaway, J. H.
English Language Book Society and Bailliere Tindall, 1984
Buku Teks
Idries Shah
Octagon Press, 1947
Buku Teks
Waxman, Jonathan, author
Springer, 2012
eBooks
Wallace, Bill, author
Aladdin Paperbacks, 2007
Buku Teks
Rees, Bill
Prentice-Hall, 1990
Buku Teks