Man pages matching name authorized_keys in section 5:

authorized_keys.5.en	debian 10 / openssh-server
authorized_keys.5.de	debian 11 / manpages-de
authorized_keys.5.en	debian 11 / openssh-server
authorized_keys.5.de	debian 12 / manpages-de
authorized_keys.5.en	debian 12 / openssh-server