Seyed Abolhasan Naeini and  Hamidreza Rahmani,  Effect of Waste Bottle Chips on Strength Parameters of Silty Soil.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    November 2017, vol. 121(1). 6 - 10
    [viewed 01 March 2021]. Available from: https://publications.waset.org/pdf/10006065.