1. Louisiana ground-water map no. 3 : potentiometric surface, 1989, and water-level changes, 1980-89, of the Sparta aquifer in north-central Louisiana Author/Creator: Geological Survey (U.S.), cartographer Publication/Creation: Baton Rouge, Louisiana : U.S. Department of the Interior, U.S. Geological Survey, 1991 Format: Map Access & Availability: Loading