Barnum, Barbara Stevens, author
An Aspen, 1995
Buku Teks
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