Lippincott, Isaac
Appleton Century Croffs, 1933
Buku Teks
Kemmerer, Donald L.
Littlefield, Adams, 1956
Buku Teks
Krooss, Herman Edward, 1912-1975
Prentice-Hall, 1955
Buku Teks
Krooss, Herman Edward, 1912-1975
Prentice-Hall, 1966
Buku Teks
Andrerson, James E.
Addison-Wesley, 1970
Buku Teks