APA (7th ed.) Citation

National Earthquake Information Center. (1991). United States National Seismograph Network. U.S. Geological Survey's National Earthquake Information Center.

Chicago Style (17th ed.) Citation

National Earthquake Information Center. United States National Seismograph Network. Denver, Colo.: U.S. Geological Survey's National Earthquake Information Center, 1991.

MLA (9th ed.) Citation

National Earthquake Information Center. United States National Seismograph Network. U.S. Geological Survey's National Earthquake Information Center, 1991.

Warning: These citations may not always be 100% accurate.