Henshaw, Richard C., author
Richard D. Irwin, 1966
Buku Teks
Copeland, Melvin T., author
Harvard University Press, 1955
Buku Teks
Bernard, Chester I., author
Harvard University Press , 1966
Buku Teks
Copeland, Melvin T., author
Harvard University Press, 1955
Buku Teks
Barnum, Barbara Stevens, author
An Aspen, 1995
Buku Teks