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Buku Teks
Dunham, Mary Frances
Bangladesh Co-operative Book Society, 1975
Buku Teks
McGivney, Veronica
The National Institute of Adult Continuing Education, 1991
Buku Teks
Tamba, Nokiamy Sesena, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2019
UI - Tugas Akhir
Oxford & IBH Pub, 1986"
Buku Teks