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In the Netherlands, four former institutes of technology have become universities over the past decades. These are the current three Technical Universities (at Delft, Eindhoven and Enschede), plus the former agricultural institute in Wageningen. A list of all hogescholen in the Netherlands, including some which might be called polytechnics, can be found here.

How many institutes of technology in the Netherlands have converted into full-fledged universities in the past few decades?
four