Man pages matching name mcd_dump_data_unregister in section 3:

mcd_dump_data_unregister.3.en	debian 10 / libminicoredumper-dev
mcd_dump_data_unregister.3.en	debian 11 / libminicoredumper-dev
mcd_dump_data_unregister.3.en	debian 12 / libminicoredumper-dev
mcd_dump_data_unregister.3.en	debian 13 / libminicoredumper-dev