Hamka (Hadji Abdul Malik Karim Amrullah), 1908-1981, author
Gema Insani, 2019
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Conlow, Rick, author
PPM, 2005
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Dewi Ningrum Kusumawidjaja, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 1976
UI - Skripsi (Membership)
Maxwell, John C., author
Mitra Media, 2002
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Kouzes, James M., author
BACA, 2008
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