On the initial spin periods of magnetars born in weak supernova explosions and their gravitational wave radiationYu-Long Yan, Quan Cheng, Xiao-Ping Zheng and Xia-Xia OuyangEur. Phys. J. C, 84 10 (2024) 1043DOI: https://doi.org/10.1140/epjc/s10052-024-13406-0