TY  - RPRT
TI  - Controlled photomosaic of the Valhalla Quadrangle of Callisto
AU  - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey
PY  - 1990
DO  - 10.3133/i1887
UR  - https://pubs.usgs.gov/publication/i1887
ID  - i1887
ER  -