City of Sydney Relationships Declaration
Other institutions such as the Registry of Births Deaths and Marriages no longer accepts an Australian Marriage Certificate as a form of ID – this creates an equal situation for both opposite sex and same sex couples as both are not allowed to present their relationship certificates as a form of ID.
Identity document
The following documents are generally considered valid (varying a little, since no law lists them): Nordic driving licence, passport (often only from EU and EFTA), national ID card from EU, Norwegian ID card from banks and some more. 
There is no ID card for anyone except bank ID card (normally printed on the reverse of a credit card). To get a bank ID card either a Nordic passport or another passport together with Norwegian residence and work permit is needed.