TY - BOOK AU - Grim, Muriel S. CN - I 19.76: CY - [Reston, VA] : CY - [Denver, Colo. : DA - 1992] ID - 241508 KW - Geological mapping KW - Geology N1 - Distributed to depository libraries in microfiche. N1 - Shipping list no.: 92-2481-M. N1 - "January 6, 1992" PB - U.S. Dept. of the Interior, U.S. Geological Survey ; PB - Books and Open-File Reports Section, distributor, PP - [Reston, VA] : PP - [Denver, Colo. : PY - 1992] T1 - An introduction to MAPGEN TI - An introduction to MAPGEN VL - 92-4 ER -