http://www.rootschat.com/forum/index.php?topic=644981.0 - just to prevent duplication.
http://www.naa.gov.au/collection/search/Search for: L M Johnson naturalisation
should be one hit in 1925.
He gives his name as "Laurence Maurice Johnson", b. Oct 31 1868, Christiania. He gives his father's name as John Gullbrensen. His mother was also Norwegian (name not given). He arrived in Australia from San Francisco in 1890 on the SS Alameda, arriving into Sydney. (exact date not given). He had resided "all over" but in Broken Hill from 1910. He had not left Australia since his arrival.
Details of wife Hannah and three kids are given (confirming it is him).
He apparently had applied for naturalisation in Adelaide soon after his arrival (says "35 years ago") and thought he was naturalised.
Now, from this we can guess that his father's is probably Johan or Jens Gulbrandsen, but I'm having trouble pinning him down.