Legal provisions for optional referendums at national level

Constitution (2011)http://www.sudantribune.com/IMG/pdf/The_Draft_Transitional_Constitution_of_the_ROSS2-2.pdf

193. (1) Pursuant to Schedule A(30) herein, the President, or the National Legislature, through a resolution passed by more than half of all its members, may refer for a referendum any matter of public interest.