@misc{indiciaee09498e21100, title = {The National Map: Topographic Maps for the 21st Century}, author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey}, year = {2002}, doi = {10.3133/fs01802}, url = {https://pubs.usgs.gov/publication/fs01802}, note = {Source identifier: fs01802} }