@article{222916, recid = {222916}, author = {Drake, Avery Ala,}, title = {Geologic map of the Piedmont in the Beltsville, Laurel, and Washington East quadrangles, Montgomery, Prince Georges, Howard, and Anne Arundel counties, Maryland, and the District of Columbia [microform] /}, publisher = {The Survey,}, address = {[Reston, Va.?] :}, pages = {1 map +}, year = {1998}, note = {Relief shown by contours and spot heights.}, url = {http://library.usi.edu/record/222916}, }