Rostow, Walt Whitman, author
A Clarion Book, 1969
Buku Teks
Stark, W.
Kegan Paul, Trench, Trubner & Co, 1947
Buku Teks
Stark, W., author
Kegan Paul, Trenck, Trubner & Co., 1947
Buku Teks
Rae, John B., author
McGraw-Hill, 1949
Buku Teks
Stebbins, Richard P.
Harper & Brothers, 1955
Buku Teks