TY  - RPRT
TI  - Modern instruments for surveying and mapping
AU  - G.D. Whitmore
AU  - M.M. Thompson
AU  - J. L. Speert
PY  - 1959
DO  - 10.1126/science.130.3382.1059
UR  - https://pubs.usgs.gov/publication/70010947
ID  - 70010947
ER  -