N. Philipova,  Mathematical Modeling of Drip Emitter Discharge of Trapezoidal Labyrinth Channel.   journal   = {International Journal of Mechanical and Industrial Engineering}, [online]. World Academy of Science, Engineering and Technology.
    February 2018, vol. 136(4). 341 - 344
    [viewed 16 April 2021]. Available from: https://publications.waset.org/pdf/10008746.