Murry, John Middleton, author
Oxford University Press, 1956
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Artikel Jurnal
Naufal Mohammad Hogantara, author
Fakultas Psikologi Universitas Indonesia , 2019
UI - Skripsi (Membership)
Epstein, E.L., author
Methuen, 1978
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Thornborrow, Joanna
New York Routledge , 1998
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