Man pages matching name unicode::collate::cjk::gb2312 in section 3perl:

Unicode::Collate::CJK::GB2312.3perl.en	debian 10 / perl-doc
Unicode::Collate::CJK::GB2312.3perl.en	debian 11 / perl-doc
Unicode::Collate::CJK::GB2312.3perl.en	debian 12 / perl-doc