@article{198862,
      recid = {198862},
      author = {Mack, Frederick K.},
      title = {The difference between the potentiometric surfaces of the  Magothy Aquifer of September 1975 and September 1990 in  southern Maryland [microform] /},
      publisher = {The Survey ;},
      address = {Towson, Md. :},
      pages = {1 map ;},
      year = {1992},
      note = {Distributed to depository libraries in microfiche.},
      url = {http://library.usi.edu/record/198862},
}