Who decides on the final form of the ballot text?

Law of Ukraine onall-Ukrainian and Local Referendums

http://www.legislationline.org/documents/action/popup/id/7114

ARTICLE 21. Adoptionof Resolution on question to Conduct the Referendum.

Having receivedthe properly validated proposal, the Verkhovna Rada of Ukraine or theappropriate local Council of peoples' deputies at its session, within onemonth, shall adopt one of the following resolutions:

1. On callingthe referendum;

2. On rejectionof the proposal to conduct a referendum, if considerable violations of thisLaw, which substantially influence the grounds to call the referendum, wererevealed;

3. On adoptionof the resolution, which is proposed in demand to call a referendum, withoutconducting the referendum itself.

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ARTICLE 22. The Content of the Resolution on calling the Referendum.

On theresolution on calling the referendum the following shall be defined: date of the referendum; thetitle of the draft of the Law or resolution; the content of the question forreferendum. […]