Artikel Jurnal
Roberts, Richard A., 1935-, author
Addison-Wesley, 1987
Buku Teks
Stetlana Ashmarina, Anabela Sarmento, Marek Vochozka; editor
Springer, 2020
Buku Teks
Tennant, Roy, author
Reed Press, 2004
Buku Teks
edited by Diane Kresh
American Library association, 2007
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