Are referendum results binding?

Electoral Commission Act (Act 51 of 1998) http://www.elections.org.za/content/WorkArea/DownloadAsset.aspx?id=987

Section 2 Application of Act

(2) Notwithstanding anything to the contrary in any other law contained, the President may, after consultation with the Commission, by proclamation in the Gazette—(a) declare that a referendum shall be held in order to ascertain the views of voters on a matter specified in the proclamation; [...]