@article{1400305,
      recid = {1400305},
      author = {Spellman, Frank R.},
      title = {Mathematics manual for water and wastewater treatment  plant operators : wastewater treatment operations : math  concepts and calculations /},
      pages = {1 online resource (255 pages) :},
      url = {http://library.usi.edu/record/1400305},
}