In dictionaries:
Popular referendum
A popular referendum, depending on jurisdiction also known as a citizens' veto, people's veto, veto referendum, citizen referendum, abrogative referendum, rejective referendum, suspensive referendum, and statute referendum,Initiative Process , ballot.org Full text.
optional referendum
The optional referendum is a referendum which comes from a request by governmental authorities or the public.
ad referendum
Subject to approval by authority.
1999 Australian republic referendum
2016 United Kingdom European Union membership referendum
2014 Scottish independence referendum
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