When a government decide to 'do' a referendum, what's the word/verb for it?

When a government decides to 'do' a referendum, what's the word/verb for it? Run, establish, form... etc?

Here is the sentence I need it for:

"The Catalan government disobeyed the Spanish constitution when they ______ a referendum in hope that Catalonia could become independent of Spain."

Solution 1:

A referendum is called (when it is first proposed) and then held (when the actual vote takes place).

According to Google ngrams:

Here's a quote from ABC News Australia concerning the 2017 Catalan independence referendum:

Catalan leaders held an independence referendum on Sunday that was banned by Madrid and marked by violent scenes at electoral stations where Spanish police sought to hinder voting.