Sisuwan Kaseamsawat and  Sivapan Choo-In,  Heavy Metal Concentration in Orchard Area, Amphawa District, Samut Songkram Province, Thailand.   journal   = {International Journal of Environmental and Ecological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    June 2014, vol. 91(7). 497 - 499
    [viewed 11 August 2020]. Available from: https://publications.waset.org/pdf/9998821.