Fine, Nathan J.
Rand McNally, 1965
Buku Teks
Fine, Nathan J.
Rand McNally, 1965
Buku Teks
Kenyon, Anne E.
Prentice-Hall, 1969
Buku Teks
McFarland, Dora
Mass. Heath , 1968
Buku Teks
Whitehead, Alfred North, 1861-1947
Oxford University Press, 1969
Buku Teks