TY  - RPRT
TI  - New reference materials for nitrogen-isotope-ratio measurements
AU  - J.K. Bohlke
AU  - C. J. Gwinn
AU  - T. B. Coplen
PY  - 2007
DO  - 10.1111/j.1751-908x.1993.tb00131.x
UR  - https://pubs.usgs.gov/publication/70188275
ID  - 70188275
ER  -