The shades of the colors show the percentage attained by the candidate who received the most votes in each commune. [*] Some communes have been colored gray to indicate that the reference document either shows that no votes were cast on such communes, or that the communes don't appear in the document altogether.
Antecedentes electorales. Volumen I. Información sobre población, electores y resultados del plebiscito de 1988, international boundaries by James2813 - Trabajo propio, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=112216215}
MP DDT