H. C. Chinwenyi and  H. D. Ibrahim and  F. A. Ahmed,  The Martingale Options Price Valuation for European Puts Using Stochastic Differential Equation Models.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    January 2020, vol. 158(2). 30 - 39
    [viewed 24 September 2020]. Available from: https://publications.waset.org/pdf/10011051.