TY - RPRT TI - Development of an 11- and 14-Digit Hydrologic Unit Boundary Layer for the Lower Mississippi-Memphis Basin Using a Geographic Information System AU - Hugh L. Nelson AU - Aimee C. Downs AU - Steve D. Crabtree AU - Doug H. Hines PY - 1997 DO - 10.3133/ofr97624 UR - https://pubs.usgs.gov/publication/ofr97624 ID - ofr97624 ER -