The information on the numbers varies between 150-200.
Records of this digital collection were assembled to document the work of the UN Special Committee on the Problem of Hungary established on January 10, 1957 by the United Nations General Assembly for the purpose of investigating the 1956 Hungarian revolution.
Records of the UN Special Committee on the Problem of Hungary: UN Documents (HU OSA 398-0-1)
"Information Available on the Alleged Executions of Hungarian Youth", 25 March 1960. HU OSA 398-0-1-6642; Records of the UN Special Committee on the Problem of Hungary: UN Documents; Open Society Archives at Central European University, Budapest.
When you cite the online source, the phrase "[Electronic record]" should be inserted into the standard citation after the item title and date. The citation should be followed by the URI with the date you last accessed the resource in square brackets.