Puerto Rico. Commonwealth Board of Elections. (1983). Results of elections, San Juan, 1904-1980.
Chicago-viite (17. p.)Puerto Rico. Commonwealth Board of Elections. Results of Elections, San Juan, 1904-1980. 1983.
MLA-viite (8. p.)Puerto Rico. Commonwealth Board of Elections. Results of Elections, San Juan, 1904-1980. 1983.
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