[1] Gao, P. X., Cyclical Behaviors of Sunspot-Group Tilt Angles in Solar Cycles 21 – 23, Solar Physics, 2023, 298, 21.
[2] Gao, P. X. & Xie, J. L., Cyclical Behavior of Magnetically Complex Sunspot Groups and Major Flares in Solar Cycles 22 – 24, Solar Physics, 2022, 297,31.
[3] Gao, P. X., Phase Relation Between Large and Simple Sunspot Groups in Solar Cycles 22 – 24, Solar Physics, 2020, 295, 23.
[4] Gao, P. X., Curious Changes in Association of Complex Sunspot Groups with X-Ray Flares (≥M1) in Solar Cycles 22–24, ApJ, 2020, 894, 77.
[5] Gao, P. X., Association of X-class flares with sunspot groups of various classes in Cycles 22 and 23, MNRAS, 2019, 484, 5692.
[6] Gao, P. X., Variations and Regularities in the Hemispheric Distributions in Sunspot Groups of Various Classes, Solar Physics, 2018, 293, 79.
[7] Gao P. X., Li, K. J., Li, F. Y., Possible Explanation of the Different Temporal Behaviors of Various Classes of Sunspot Groups, Solar Physics, 2017, 292, 124.
[8] Gao, P. X., Periodicity of sunspot group number during the Maunder Minimum, MNRAS, 2017, 472, 2913.
[9] Gao, P. X., LONG-TERM TREND OF SUNSPOT NUMBERS, ApJ, 2016, 830, 140.
[10] Gao, P. X., & Xu, J. X., Solar flare count periodicities in different X-ray flare classes, MNRAS, 2016, 457, 2839.
