APA Style
      Dai, S. et al (2017).
    Mineral Matter and Trace Elements in Coal .
    Basel:
  MDPI - Multidisciplinary Digital Publishing Institute.
  
MLA Style
      Dai, Shifeng. et al.
    "Mineral Matter and Trace Elements in Coal".
    
    Basel:
  MDPI - Multidisciplinary Digital Publishing Institute,
  2017.
  Text.