Optional referendum

1 If within 100 days of the official publication of the enactment any 50,000 persons eligible to vote or any eight Cantons request it, the following shall be submitted to a vote of the People:

a. federal acts;

b. emergency federal acts whose term of validity exceeds one year;

c. federal decrees, provided the Constitution or an act so requires;

d. international treaties that:

1. are of unlimited duration and may not be terminated,

2. provide for accession to an international organisation,

3. contain important legislative provisions or whose implementation requires the enactment of federal legislation.

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