Digital elevation models : data users guide 5 за авторством United States. Department of Interior. US Geological Survey

Land use and land cover digital data from 1 : 250,000 - and 1 : 100,000 - scale maps за авторством United States. Department of Interior. US Geological Survey

Process design manual for land treatment of municipal wastewater / за авторством United States. Department of Interior, United States. Department of Agriculture, United States. Environmental Protection Agency, United States. Army. Corps of Engineers