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

Suriname

Article 54 of Suriname’s Constitution gives adult citizens over the age of 18 the right to vote as long as they are registered voters. Articles 57 and 58 states that citizens have the right to vote for the members of the National Assembly barring their right to vote has not been revoked by the courts (Constitute Project, “Suriname’s Constitution of 1987 with Amendments through 1992”).

Voting Rights and Suffrage · Country sources (all rights) · Years mentioned: 1987, 1992 · Last edited 2022-12-28 · Edit on GitHub