Lefever, Katrien
T.M.C. Asser Press, 2012
eBooks
Hudson, Robert V., author
Garland publishing, 1987
Buku Referensi
edited by Jay G. Blumler and Elihu Katz
Sage, 1974
Buku Teks
Ahuja, B. N., author
Surjeet Publications, 1989
Buku Teks
Vivian, John, author
Pearson, 2011
Buku Teks