Ahmad, N., Radin Umar, R., Halim, I., Mohamed, M., Jamli, M.R., Baharudin, M.S. and Hamid, M. 2018. Evaluation of Menu Hierarchy Display Types in Self-Checkout System: Effects on Human Performance. Journal of Advanced Manufacturing Technology (JAMT). 12, 1(1) (May 2018), 371–382.