@article{53603,
      note = {Cover title.},
      author = {North, William G.},
      url = {http://library.usi.edu/record/53603},
      title = {The Middle Devonian strata of southern Illinois},
      publisher = {Illinois State Geological Survey,},
      recid = {53603},
      pages = {45 p.},
      address = {Urbana,},
      year = {1969},
}