The pole problem: A persistent challenge in spherical harmonic applications
LI Huijun, CHENG Wei, CAI Qifa, GUO Bing, GE Panze , LI Fei, YANG Hongyang, YU Qian
Chinese Journal of Polar Research . 2026, (2): 242 -252 .  DOI: 10.13679/j.jdyj.20250082