1991 Latvian independence and democracy referendum
An independence referendum was held in the Latvian SSR on 3 March 1991, alongside a similar referendum in the Estonian SSR the same day. Known as the "Popular Survey about the independence of the Republic of Latvia", voters were asked "are you in favour of a democratic and independent Republic of Latvia".
Source: Wikipedia — 1991 Latvian independence and democracy referendum (CC BY-SA 4.0)