Yan Wang and  Yasushi Asami and  Yukio Sadahiro,  A Research on Inference from Multiple Distance Variables in Hedonic Regression – Focus on Three Variables.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2015, vol. 100(4). 450 - 459
    [viewed 15 October 2019]. Available from: https://publications.waset.org/pdf/10001092.