1. Scanned 250k Scale Topographic Maps (Decollared), Arizona, 1970 to 1995 Imagery University Of Arizona Public content unfold_more 1970. United State. Geological Survey. This data set originated as a Digital Raster Graphic (DRG) produced from a scanned USGS topographic map. The DRG included the collar information an... United State. Geological Survey.
