Kwok Tak Kit,  Circular Economy: Relationship of the Natural Water Collection System, Afforestation and Country Park towards Environmental Sustainability.   journal   = {International Journal of Environmental and Ecological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2022, vol. 183(3). 54 - 60
    [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/10012491.