1. US Geological Survey; Denver CO USA
2. Department of Geosciences; Colorado State University; Fort Collins Colorado USA
3. Albuquerque Seismological Laboratory; USGS Albuquerque New Mexico
4. Boone Pickens School of Geology; Oklahoma State University; Stillwater Oklahoma USA
5. Department of Earth and Atmospheric Sciences; Saint Louis University; St. Louis Missouri USA
6. Global Seismological Services; Golden Colorado USA