Rauno Pääkkönen and  Fabriziomaria Gobba and  Leena Korpinen,  LED Lighting Interviews and Assessment in Forest Machines.   journal   = {International Journal of Medical and Health Sciences}, [online]. World Academy of Science, Engineering and Technology.
    July 2015, vol. 105(9). 673 - 676
    [viewed 22 October 2021]. Available from: https://publications.waset.org/pdf/10002146.