Titchmarsh, E, C.
Chelsea Publishing Company, 1990
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Muhammad Iqbal Ramadhan
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2019
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Fuller, Wayne A.
John Wiley & Sons, 1976
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Yan, Wei Qi
Springer International Publishing, 2016
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Cole, Alison
Dorling Kindersley Book, 1993
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