Socialist Single Front (Spanish: Frente Único Socialista, FUS) was a Bolivian electoral political alliance of left-wing and socialist political parties and organizations.
The Socialist Single Front was established on 18 February 1938, for the 1938 congressional elections, by these parties: The Socialist Single Front was associated with the revolutionary government of Colonel Germán Busch Becerra and elected majority deputies of the new Constituent Assembly.
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