Long, Y., L. H. Lee, E. P. CHEW, Y. LUO, J. SHAO, A. SENGUTA, and S. M. L. Chua. “OPERATION PLANNING FOR EMPTY CONTAINER REPOSITIONING”. International Journal of Industrial Engineering: Theory, Applications and Practice, vol. 20, no. 1-2, Mar. 2013, doi:10.23055/ijietap.2013.20.1-2.478.