Literature Mapper is a plugin for QGIS that connects QGIS to a Zotero citation database, allowing the user to add georeferences to individual citations. The documentation is here. Please don't hesitate to file an issue. Additionally, the current developers would very much appreciate help implementing the enhancements and bug fixes listed in the issues list.
mjstoroz/LiteratureMapper
A QGIS plugin to add geoJSON geometries to records in a Zotero library
PythonGPL-2.0