Hall, D.G.E.
Hutchinson's University Library, 1950
Buku Teks SO
Hall, D.G.E.
University of Pennsylvani Press, 1971
Buku Teks SO
Hall, D.G.E.
London, Hutahinson University Library, (1960)
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Dwiyoga Subarkah
Fakultas Ilmu Pengetahuan Budaya Universitas Indonesia, 2010
UI - Skripsi Open
Archer, Geoffrey
Arrow, 2002
Buku Teks SO