Man pages matching name gd::barcode::ean13 in section 3pm:

GD::Barcode::EAN13.3pm.en	debian 10 / libgd-barcode-perl
GD::Barcode::EAN13.3pm.en	debian 11 / libgd-barcode-perl
GD::Barcode::EAN13.3pm.en	debian 12 / libgd-barcode-perl
GD::Barcode::EAN13.3pm.en	debian 13 / libgd-barcode-perl