L.1.11.1 Header Part

Header information in a WordprocessingML document is stored in a header part within the package, which is stored via an implicit relationship from the Main Document part or the Glossary Document part of relationship type http://purl.oclc.org/ooxml/officeDocument/relationships/header and has a content type of vnd-openxmlformats.officedocument.wordprocessingml-header+xml.