F. Keller and  G. Reinhart,  Systematic Approach for Energy-Supply-Orientated Production Planning.   journal   = {International Journal of Industrial and Manufacturing Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2015, vol. 103(7). 2417 - 2422
    [viewed 16 April 2024]. Available from: https://publications.waset.org/pdf/10002043.