Jin Xu and  Albert Y.S. Lam and  Victor O.K. Li,  Stock Portfolio Selection Using Chemical Reaction Optimization.   journal   = {International Journal of Chemical and Molecular Engineering}, [online]. World Academy of Science, Engineering and Technology.
    May 2011, vol. 53(5). 409 - 414
    [viewed 16 December 2019]. Available from: https://publications.waset.org/pdf/11346.