APA Style
      Wu, S, F. (2015).
    The Helmholtz Equation Least Squares Method (1).
    Springer New York, NY:
  Springer New York, NY.
  
MLA Style
      Wu, Sean, F..
    "The Helmholtz Equation Least Squares Method".
    1
    Springer New York, NY:
  Springer New York, NY,
  2015.
  Text.