O`Sullivan, Jeremiah Francis, 1903-, author
Appleton Century Croffs, 1943
Buku Teks
Hollister, C. Warren, author
John Wiley & Sons, 1968
Buku Teks
Lewis, Archibald R. (Archibald Ross), 1914-1990, author
Alfred A. Knopf, 1969
Buku Teks
Davis, H. W. C.
Oxford University Press, 1960
Buku Teks
Marcucci, Luisa, author
Studio Books , 1960
Buku Referensi