@book{ Solr-3205324, title = {Geologic map index of Iowa}, series = {Its Index to geologic mapping in the United States}, editor = {Geological Survey (U.S.)}, editor = {Boardman, Leona, 1894-1957}, editor = {Brown, Annabel}, address = {Washington,}, year = {1948}, note = {"Key to Index map" (bibliography of 103 maps) in margin.}, }