1. Calculation of coal resources using ARC/INFO and EarthVision : methodology for the National Coal Resource Assessment Author/Creator: Roberts, Laura N. Robinson Publication/Creation: Denver, CO : U.S. Dept. of the Interior, U.S. Geological Survey, 1999 Resource Type: Book Edition: Paper version. Access & Availability: Loading
2. Paleogeography of the Late Cretaceous of the western interior of middle North America : coal distribution and sediment accumulation Author/Creator: Roberts, Laura N. Robinson Publication/Creation: Washington : U.S. G.P.O. ; Denver, CO : U.S. Geological Survey, Information Services, 1995 Resource Type: Book Access & Availability: Loading