M. Tawfik and  X. Tonnellier and  C. Sansom,  Parameters Influencing the Output Precision of a Lens-Lens Beam Generator Solar Concentrator .   journal   = {International Journal of Energy and Power Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2017, vol. 124(4). 428 - 436
    [viewed 24 April 2024]. Available from: https://publications.waset.org/pdf/10007114.