TY  - RPRT
TI  - Some natural variations in the relative abundance of copper isotopes
AU  - Edward C. Walker
AU  - Frank Cuttitta
AU  - F. E. Senftle
PY  - 1957
DO  - 10.3133/tei696
UR  - https://pubs.usgs.gov/publication/tei696
ID  - tei696
ER  -