Man pages matching name gnupg::signature in section 3pm:

GnuPG::Signature.3pm.en	debian 10 / libgnupg-interface-perl
GnuPG::Signature.3pm.en	debian 11 / libgnupg-interface-perl
GnuPG::Signature.3pm.en	debian 12 / libgnupg-interface-perl