Lund, Philip J., author
Oliver & Boyd, 1971
Buku Teks
Downs, Anthony, author
Harper and Row, 1975
Buku Teks
Myint, Hla, author
Oxford University Press, 1971
Buku Teks
Willett, Allan H., author
University of Pennsylvania Press, 1951
Buku Teks
Chamberlain, Neil W. (Neil Wolverton), author
Harper & Brothers , 1955
Buku Teks