Armstrong, Michael
Gramedia, 2003
Buku Teks
McSweeney, Edward
Pustaka Binaman Pressindo, 1985
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Andrews, jean
Course Technology, 2013
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Armstrong, Michael
[Publisher not identified], [Date of publication not identified]
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Muhammad Ezra Arrazaq Irvan
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2023
UI - Tugas Akhir