Bao Rong Chang, Hsiu-Fen Tsai, and Hsia-Chung Huang, “Implementation of Smart Mobile Point-of-Sale Cash Register System,” Journal of Network Intelligence, Vol. 3, No. 3, pp. 170-188, August 2018. (EI) (MOST 105-2221-E-390-013-MY3 & MOST 105-2622-E-390-007-CC3)