Man pages matching name shishi_apreq_mutual_required_p in section 3:

shishi_apreq_mutual_required_p.3.en	debian 10 / shishi-doc
shishi_apreq_mutual_required_p.3.en	debian 11 / shishi-doc
shishi_apreq_mutual_required_p.3.en	debian 12 / shishi-doc