Tru C. Le and  France Cheong,  Measuring Risk Levels and Efficacy of Risk Management Strategies in Vietnamese Catfish Farming.   journal   = {International Journal of Economics and Management Engineering}, [online]. World Academy of Science, Engineering and Technology.
    September 2009, vol. 33(9). 1744 - 1755
    [viewed 20 October 2019]. Available from: https://publications.waset.org/pdf/15509.