TY  - RPRT
TI  - Twentieth annual report of the United States Geological Survey, 1898-1899: Part I - Director's report including triangulation and spirit leveling
AU  - Charles D. Walcott
PY  - 1899
DO  - 10.3133/ar20_1
UR  - https://pubs.usgs.gov/publication/ar20_1
ID  - ar20_1
ER  -