Webster, Hutton, author
D.C. Heath, 1947
Buku Teks
Hoffman, Ross J.S., author
Littlefield, Adams, 1958
Buku Teks
Cobban, Alfred, author
Braziller, 1965
Buku Teks
Hauser, Arnold, author
Alfred A. Knopf , 1952
Buku Teks
Hoffding, Harold, author
Dover, 1955
Buku Teks