- Additional religious affiliations from http://www.adherents.com/adh_congress.html
- Face++ Cognitive Services API
- Czech Republic Parliamentary Members Archive
- Germany Bundestag Open Data
- Spain Parliamentary Members Archive
- Additional Twitter handles from https://github.com/oduwsdl/US-Congress
- Additional Twitter handles provided by Bruno Castanho Silva and Sven-Oliver Proksch
- Wikimedia Commons
- Wikimedia API
- Wikidata API
- Wikipedia
- Wikipedia API