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Sources/Entities: SGMAI - Electoral Registration Database (registered voters) | SGMAI - Data from the provisional count (voters: 1976 and from 2000 onwards) | CNE - Final data (voters: from 1980 until 1996), PORDATA
Sources/Entities: SGMAI - Electoral Registration Database (registered voters) | SGMAI - Data from the provisional count (voters: 1976 and from 2000 onwards) | CNE - Final data (voters: from 1980 until 1996), PORDATA