Nau, Henry R., 1941-, author
SAGE Publications, 2019
Buku Teks
Claude, Inis L., author
Random House , 1976
Buku Teks
Cottle, Simon, author
Sage, 2003
Buku Teks
Bartlett, Ruhl
Hill and Wang, 1963
Buku Teks
Claude, Inis L., author
Random House, 1964
Buku Teks