WASET
    Osman Acar,  Two Degree of Freedom Spherical Mechanism Design for Exact Sun Tracking .   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    January 2016, vol. 109(1). 186 - 191
    [viewed 09 May 2024]. Available from: https://publications.waset.org/pdf/10003527.