Man pages matching name ppix::regexp::node::unknown in section 3pm:

PPIx::Regexp::Node::Unknown.3pm.en	debian 10 / libppix-regexp-perl
PPIx::Regexp::Node::Unknown.3pm.en	debian 11 / libppix-regexp-perl
PPIx::Regexp::Node::Unknown.3pm.en	debian 12 / libppix-regexp-perl