Legal provisions for mandatory referendums at national level

1987 CONSTITUTION OF THE REPUBLICOF THE PHILIPPINES

http://www.chanrobles.com/philsupremelaw1.htm

ARTICLE XVII:AMENDMENTS AND REVISIONS?

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Sec.4. Any amendment to, or revision of, this Constitution under Section 1 hereofshall be valid when ratified by a majority of the votes cast in a plebiscitewhich shall be held not earlier than sixty days nor later than ninety daysafter the approval of such amendment or revision.

Anyamendment under Section 2 hereof shall be valid when ratified by a majority ofthe votes cast in a plebiscite which shall be held not earlier than sixty daysnor later than ninety days after the certification by the Commission onElections of the sufficiency of the petition.