What is the oldest written source in this country that mentions this right?

Guinea

Under Guinea’s Constitution, the President and members of the legislature are elected via free, equal, direct, and secret elections. All citizens are allowed to vote as long as they are over 18 and meet citizenship requirements. (Constitute Project, “Guinea’s Constitution of 2010”).

Voting Rights and Suffrage · Country sources (all rights) · Years mentioned: 2010 · Last edited 2022-12-28 · Edit on GitHub