Wong, A. (2020, January 14). eWallet Comparison: Grab vs Touch ‘n Go vs Boost.
Retrieve from https://www.soyacincau.com/2020/01/14/ewallet-comparison-grabtouch-n-go-boost/

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Code Class (2019) PHP for Beginners to Inventory POS Sales Project – AdminLTE.
Retrieved from https://www.youtube.com/watch?v=tuOhq53Kb5M

YukCoding Media (2020) Seri Membuat App POS (Point of Sales) Pro [CI3,Bootstrap]
Retrieved from https://www.youtube.com/playlist?list=PLTagRbmJ8etsYolfn4DTCg8I6rfDivklc

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