1. Haley & Aldrich, Inc., 1956 Webster Street, Suite 300, Oakland, California 94612, United States
2. Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina 27695, United States
3. Environmental Isotope Laboratory, University of Waterloo, Waterloo, ON N2L 3G1, Canada
4. Haley & Aldrich, Inc., 400 East Van Buren Street, Suite 545, Phoenix, Arizona 85004, United States
5. ECT2, Inc., 200 Town Center Drive, Suite 2, Rochester, New York 14263, United States
6. Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada