68 citations as recorded by crossref.

1. VLF/LF Amplitude Perturbations before Tuscany Earthquakes, 2013 B. Khadka et al. https://doi.org/10.4236/ns.2017.912041
2. Precursors signatures of few major earthquakes in Italy using very low frequency signal of 45.9 kHz K. Kandel et al. https://doi.org/10.1007/s11600-019-00316-z
3. Statistical Evaluations of Variations in Dairy Cows’ Milk Yields as a Precursor of Earthquakes H. Yamauchi et al. https://doi.org/10.3390/ani7030019
4. The Study on Anomalies of the Geomagnetic Topology Network Associated with the 2022 Ms6.8 Luding Earthquake Z. Yu et al. https://doi.org/10.3390/rs16091613
5. VLF/LF Radio Sounding of Ionospheric Perturbations Associated with Earthquakes M. Hayakawa https://doi.org/10.3390/s7071141
6. Unusual behaviour of VLF signal parameters before the devastating Nepal earthquake of 25th April, 2015 A. Choudhury et al. https://doi.org/10.1007/s12648-025-03656-3
7. Contaminated Effect of Geomagnetic Storms on Pre-Seismic Atmospheric and Ionospheric Anomalies during Imphal Earthquake S. Biswas et al. https://doi.org/10.4236/ojer.2020.95022
8. Predicting the unpredictable; evidence of pre‐seismic anticipatory behaviour in the common toad R. Grant & T. Halliday https://doi.org/10.1111/j.1469-7998.2010.00700.x
9. Lithosphere–Atmosphere–Ionosphere Coupling Effects Based on Multiparameter Precursor Observations for February–March 2021 Earthquakes (M~7) in the Offshore of Tohoku Area of Japan M. Hayakawa et al. https://doi.org/10.3390/geosciences11110481
10. Variation in the VLF signal noise amplitude during the period of intense seismic activity in Central Italy from 25 October to 3 November 2016 A. Nina et al. https://doi.org/10.3389/fenvs.2022.1005575
11. Precursory effects in the nighttime VLF signal amplitude for the 18th January, 2011 Pakistan earthquake S. Ray et al. https://doi.org/10.1007/s12648-012-0014-5
12. Investigation of the relationship between ionospheric foF2 and earthquakes T. Karaboga et al. https://doi.org/10.1016/j.asr.2018.01.015
13. On the generation of narrow‐banded ULF/ELF pulsations in the lower ionospheric conducting layer V. Sorokin & M. Hayakawa https://doi.org/10.1029/2008JA013094
14. Review of Subionospheric VLF/LF Radio Signals for the Study of Seismogenic Lower-Ionospheric Perturbations M. Hayakawa https://doi.org/10.3390/atmos16111312
15. A statistical study on the correlation between lower ionospheric perturbations as seen by subionospheric VLF/LF propagation and earthquakes M. Hayakawa et al. https://doi.org/10.1029/2009JA015143
16. The 25 April 2015 Nepal Earthquake: Investigation of precursor in VLF subionospheric signal A. Maurya et al. https://doi.org/10.1002/2016JA022721
17. Disturbances of Subionospheric Electromagnetic Signals and Strong Earthquakes (from Observations on the Kamchatka Peninsula in 2023–2024) M. Solovieva et al. https://doi.org/10.1134/S1069351325700922
18. Air ionization at rock surfaces and pre-earthquake signals F. Freund et al. https://doi.org/10.1016/j.jastp.2009.07.013
19. An Amateur-Radio-Based Open-Source (HW/SW) VLF/LF Receiver for Lower Ionosphere Monitoring, Examples of Identified Perturbations F. Malkotsis et al. https://doi.org/10.3390/foundations2030044
20. VLF Signal Noise Reduction during Intense Seismic Activity: First Study of Wave Excitations and Attenuations in the VLF Signal Amplitude A. Nina https://doi.org/10.3390/rs16081330
21. Ionospheric anomalies detected by ionosonde and possibly related to crustal earthquakes in Greece L. Perrone et al. https://doi.org/10.5194/angeo-36-361-2018
22. A multi-experiment approach to ascertain electromagnetic precursors of Nepal earthquakes S. Sharma et al. https://doi.org/10.1016/j.jastp.2019.105163
23. A Critical Review of Ground Based Observations of Earthquake Precursors L. Conti et al. https://doi.org/10.3389/feart.2021.676766
24. Ionospheric perturbations due to earthquakes as determined from VLF and GPS-TEC data analysis at Agra, India D. Singh et al. https://doi.org/10.1016/j.asr.2017.11.017
25. Geospace perturbations induced by the Earth: The state of the art and future trends A. De Santis et al. https://doi.org/10.1016/j.pce.2015.05.004
26. Advances and challenges in the study of ULF geomagnetic anomalies for earthquake precursors: A four-decade critical literature review E. Winata et al. https://doi.org/10.1016/j.eqrea.2025.100438
27. Reply to Comment on “Preseismic lithosphere‐atmosphere‐ionosphere coupling” M. Kamogawa https://doi.org/10.1029/2007EO230009
28. On the statistical correlation of over-horizon VHF signals with meteorological radio ducting and seismicity N. Yonaiguchi et al. https://doi.org/10.1016/j.jastp.2007.01.007
29. Correlation of earthquake occurrence among major fault zones in the eastern margin of the Tibetan Plateau through Big Data Analysis H. Zhang et al. https://doi.org/10.59717/j.xinn-geo.2025.100145
30. Multi-Parameter Observations of Seismogenic Phenomena Related to the Tokyo Earthquake (M = 5.9) on 7 October 2021 M. Hayakawa et al. https://doi.org/10.3390/geosciences12070265
31. Changes in animal activity prior to a major (M= 7) earthquake in the Peruvian Andes R. Grant et al. https://doi.org/10.1016/j.pce.2015.02.012
32. Reduction of the VLF Signal Phase Noise Before Earthquakes A. Nina et al. https://doi.org/10.3390/atmos12040444
33. Characteristic Variations of VLF/LF Signals during a High Seismic Activity in Japan in November 2016 T. Asano et al. https://doi.org/10.4236/ojer.2017.64013
34. A statistical study on the AGW modulations in subionospheric VLF/LF propagation data and consideration of the generation mechanism of seismo-ionospheric perturbations Y. Kasahara et al. https://doi.org/10.1541/jae.30.103
35. Solar–terrestrial, ionospheric and natural phenomena studies using the South America VLF network (SAVNET) J. Raulin et al. https://doi.org/10.1016/j.jastp.2010.11.029
36. On precursors to the Italy earthquake M.6.2 using VLF signal of NSY(45.9 kHz) received at Kiel Longwave Monitor K. Kandel et al. https://doi.org/10.1007/s11600-017-0087-9
37. Stable and unstable plasma perturbations in the ionospheric F region, caused by spatial packet of atmospheric gravity waves Y. Rapoport et al. https://doi.org/10.1016/j.pce.2008.09.001
38. Earthquake precursors in the light of peroxy defects theory: Critical review of systematic observations F. Freund et al. https://doi.org/10.1140/epjst/e2020-000243-x
39. Subionospheric VLF/LF monitoring of ionospheric perturbations for the 2004 Mid-Niigata earthquake and their structure and dynamics T. Yamauchi et al. https://doi.org/10.1016/j.jastp.2007.02.002
40. Current Status of Seismo Electromagnetics as Short-term Earthquake Prediction M. HAYAKAWA https://doi.org/10.1541/ieejjournal.130.431
41. Ionospheric perturbations related to the Miyagi-oki earthquake on 16 August 2005, as seen from Japanese VLF/LF subionospheric propagation network F. Muto et al. https://doi.org/10.1016/j.pce.2008.09.010
42. Unusual Animal Behavior Preceding the 2011 Earthquake off the Pacific Coast of Tohoku, Japan: A Way to Predict the Approach of Large Earthquakes H. Yamauchi et al. https://doi.org/10.3390/ani4020131
43. Short-term earthquake prediction: Current status of seismo-electromagnetics S. Uyeda et al. https://doi.org/10.1016/j.tecto.2008.07.019
44. A statistical analysis of seismo-ionospheric TEC anomalies before 63 Mw ≥ 5.0 earthquakes in Turkey during 2003–2016 E. Şentürk & M. Çepni https://doi.org/10.1007/s11600-018-0214-2
45. West Pacific Earthquake Forecasting Using NOAA Electron Bursts With Independent L-Shells and Ground-Based Magnetic Correlations C. Fidani https://doi.org/10.3389/feart.2021.673105
46. On the Relative Effect of Magnitude and Depth of Earthquakes in the Generation of Seismo-Ionospheric Perturbations at Middle Latitudes as Based on the Analysis of Subionospheric Propagation Data of JJY (40 kHz)-Kamchatka Path M. Hayakaw et al. https://doi.org/10.4236/ojer.2013.22003
47. On the Tempo-Spatial Evolution of the Lower Ionospheric Perturbation for the 2016 Kumamoto Earthquakes from Comparisons of VLF Propagation Data Observed at Multiple Stations with Wave-Hop Theoretical Computations T. Asano & M. Hayakawa https://doi.org/10.4236/ojer.2018.73010
48. Ionosonde Data Analysis in Relation to the 2016 Central Italian Earthquakes A. Ippolito et al. https://doi.org/10.3390/geosciences10090354
49. Toward a unified solid state theory for pre-earthquake signals F. Freund https://doi.org/10.2478/s11600-009-0066-x
50. Measurement of Doppler shifts of short-distance subionospheric LF transmitter signals and seismic effects S. Asai et al. https://doi.org/10.1029/2010JA016055
51. Preseismic Perturbations and their Inhomogeneity as Computed from Ground‐ and Space‐Based Investigation during the 2016 Fukushima Earthquake S. Biswas et al. https://doi.org/10.1155/2023/7159204
52. Studies of seismo-ionospheric correlations using anomalies in phase of very low frequency signal P. Pal et al. https://doi.org/10.1080/19475705.2016.1161666
53. Probing the lower ionospheric perturbations associated with earthquakes by means of subionospheric VLF/LF propagation M. Hayakawa https://doi.org/10.1007/s11589-011-0823-1
54. Subionospheric VLF perturbations observed at low latitude associated with earthquake from Indonesia region A. Kumar et al. https://doi.org/10.1016/j.jastp.2013.04.011
55. Variation in natural short-period ionospheric noise, and acoustic and gravity waves revealed by the amplitude analysis of a VLF radio signal on the occasion of the Kraljevo earthquake (Mw = 5.4) A. Nina et al. https://doi.org/10.1016/j.scitotenv.2019.136406
56. Disturbances of sub-ionospheric electromagnetic signals and strong earthquakes (based on observations on the Kamchatka Peninsula in 2023–2024) M. Solovieva et al. https://doi.org/10.21455/gr2025.1-2
57. Transient Effects in Atmosphere and Ionosphere Preceding the 2015 M7.8 and M7.3 Gorkha–Nepal Earthquakes D. Ouzounov et al. https://doi.org/10.3389/feart.2021.757358
58. The wave-like structures of ionospheric perturbation associated with Sumatra earthquake of 26 December 2004, as revealed from VLF observation in Japan of NWC signals T. Horie et al. https://doi.org/10.1016/j.jastp.2007.03.012
59. Detection of Effects of Shallow Major Earthquakes (M ≥ 5.0, depth ≤ 30 km) Occurred in India, Nepal, and China on Ionosphere Using Statistical Approaches R. Singh et al. https://doi.org/10.1134/S0016793224600887
60. Pre-earthquake signals: Underlying physical processes F. Freund https://doi.org/10.1016/j.jseaes.2010.03.009
61. A Six-Year (2014–2020) Statistical Correlation Study of VLF Terminator Time Shift with Earthquakes in Japan D. Politis et al. https://doi.org/10.3390/rs16224162
62. On the correlation between ionospheric perturbations as detected by subionospheric VLF/LF signals and earthquakes as characterized by seismic intensity M. Hayakawa et al. https://doi.org/10.1016/j.jastp.2010.05.009
63. Atmospheric gravity waves as a possible candidate for seismo-ionospheric perturbations M. Hayakawa et al. https://doi.org/10.1541/jae.31.129
64. On the biophysical mechanism of sensing upcoming earthquakes by animals D. Panagopoulos et al. https://doi.org/10.1016/j.scitotenv.2020.136989
65. Possible Pre-Seismic Indications Prior to Strong Earthquakes That Occurred in Southeastern Mediterranean as Observed Simultaneously by Three VLF/LF Stations Installed in Athens (Greece) D. Politis et al. https://doi.org/10.3390/atmos14040673
66. Unusual behavior of Very Low Frequency signal during the earthquake at Honshu/Japan on 11 March, 2011 S. Sasmal et al. https://doi.org/10.1007/s12648-014-0520-8
67. Current status of seismo-electromagnetics for short-term earthquake prediction M. Hayakawa & Y. Hobara https://doi.org/10.1080/19475705.2010.486933
68. Looking for Earthquake Precursors From Space: A Critical Review P. Picozza et al. https://doi.org/10.3389/feart.2021.676775