WASET
    A. M. Hasna,  Energy Efficiency: An Engineering Pathway towards Sustainability.   journal   = {International Journal of Humanities and Social Sciences}, [online]. World Academy of Science, Engineering and Technology.
    June 2009, vol. 30(6). 752 - 760
    [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/5131.