Böhlke, J.K., Gwinn, C.J., and Coplen, T.B., 1993, New reference materials for nitrogen-isotope-ratio measurement: Geostandards Newsletter, v. 17, p. 159-164. (on-line abstract)
Coplen, T.B., 1993, Uses of environmental isotopes, in Alley, W.M., ed., Regional ground-water quality: New York, Van Nostrand Reinhold, p. 227-254.
Dunkle, S.A., Plummer, L.N., Busenberg, E., Phillips, P.J., Denver, J.M., Hamilton, P.A., Michel, R.L., and Coplen, T.B., 1993, Chlorofluorocarbons (CC13F and CC12F2) as dating tools and hydrologic tracers in shallow ground water of the Delmarva Peninsula, Atlantic Coastal Plain, USA Chlorofluorocarbons (CC13F and CC12F2) as dating tools and hydrologic tracers in shallow ground water of the Delmarva Peninsula, Atlantic Coastal Plain, USA
Keir, R.S., and Michel, R.L., 1993, Interface dissolution control of core top radiocarbon age: Geochimica et Cosmochimica Acta, v. 57, p. 3563-3574.
Landwehr, J.M., Winograd, I.J., Coplen, T.B., Riggs, A.C., Ludwig, K.R., and Szabo, B.J., 1993, Stochastic analysis of delta 0-18 and delta C-13 time series found in a continuous 500,000-year climatic record from Great Basin Vein Calcite, in Kelmelis, J.A., and Snow, M., eds., Proceeding of the U.S. Geological Survey Global Change Research Forum, Herndon, VA: U.S. Geological Survey Circular 1086, p. 86.
Naftz, D.L., Michel, R.L., and Miller, K.A., 1993, Isotopic indicators of climate in ice cores, Wind River Range, Wyoming, in Swart, P.K., Lohman, K.C., McKenzie, J., and Savin, S., eds., Climate Change in Continental Isotopic Records, Geophysical Monograph 78, p. 55-66.
Plummer, L.N., Michel, R.L., Thurman, E.M., and Glynn, P.D., 1993, Environmental tracers for age-dating young groundwater, in Alley, W.M., ed., Regional Ground-Water Quality: New York, Van Nostrand Reinhold, p. 255-294.
Schroeder, R.A., Martin, P., and Böhlke, J.K., 1993, Chemical, isotopic, and microbiological evidence for denitrification during transport of domestic wastewater through a thick unsaturated zone in the Mojave Desert, San Bernardino County, California: U.S. Geological Survey Open-File Report 93-414, 10p. (on-line abstract)
Sturchio, N.C., Böhlke, J.K., and Markun, F.J., 1993, Radium isotope geochemistry of thermal waters, Yellowstone National Park, Wyoming: Geochimica et Cosmochimica Acta, v. 57, p. 1203- 1214. (on-line abstract)