@article{122190,
      author = {Kier, Porter M.},
      url = {http://library.usi.edu/record/122190},
      title = {Upper Miocene echinoids from the Yorktown Formation of  Virginia and their environmental significance},
      publisher = {Smithsonian Institution Press; [for sale by the Supt. of  Docs., U.S. Govt. Print. Off.]},
      recid = {122190},
      pages = {41 p.},
      address = {Washington,},
      year = {1972},
}