Are referendum results binding?

Mozambique
Answer
Optional referendum - always
Source
Constitution of theRepublic of Mozambique
(adopted in 2004)
(English translation)
http://confinder.richmond.edu/admin/docs/Constitution_(in_force_21_01_05)(English)-Mozlegal.pdf
Article 136(6).
A referendum shall be considered valid and binding only where at leasthalf of the registered voters have voted in it.