Alexander Urbach and  Mukharbij Banov and  Vladislav Turko,  The Fatigue Damage Accumulation on Systems of Concentrators.   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    November 2011, vol. 59(11). 2164 - 2169
    [viewed 24 January 2020]. Available from: https://publications.waset.org/pdf/4448.