M. Belén Prendes-Gero and  Celestino González-Nicieza and  M. Inmaculada Alvarez-Fernández,  Modelling for Roof Failure Analysis in an Underground Cave.   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    September 2020, vol. 166(10). 498 - 504
    [viewed 26 October 2021]. Available from: https://publications.waset.org/pdf/10011504.