pdfsync – Provide links between source and PDF

The pack­age runs with pdfTeX or X∃TeX, and cre­ates an aux­il­iary file with ge­o­met­ri­cal in­for­ma­tion to per­mit ref­er­ences back and forth be­tween source and PDF, as­sum­ing a con­form­ing ed­i­tor and PDF viewer.