Hyderabad, India. National Geophysical Research Institute. Geoelectric Observatory, Srivastava, V. B., Ranga Rao, M., & Lakshmi, A. (1973). Rapid variations of earth's electromagnetic field, January-December 1975: Report of the Geoelectric Observatory. National Geophysical Research Institute.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Hyderabad, India. National Geophysical Research Institute. Geoelectric Observatory, Vinod Behari Srivastava, M. Ranga Rao, و A. Lakshmi. Rapid Variations of Earth's Electromagnetic Field, January-December 1975: Report of the Geoelectric Observatory. Hyderabad (India): National Geophysical Research Institute, 1973.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Hyderabad, India. National Geophysical Research Institute. Geoelectric Observatory, et al. Rapid Variations of Earth's Electromagnetic Field, January-December 1975: Report of the Geoelectric Observatory. National Geophysical Research Institute, 1973.