A. Delgoshaei, M. K. Ariffin, B. T. H. T. Bin Baharudin, and Z. Leman, “A Backward Approach for Maximizing Net Present Value of Multi-mode Pre-emptive Resource-Constrained Project Scheduling Problem with Discounted Cash Flows Using Simulated Annealing Algorithm”, Int J Ind Eng Manag, vol. 5, no. 3, pp. 151–158, Sep. 2014.