Hi James,

Referencing a computer program is a bit like referencing a movie.

In-text you would list the name of the program in italics and the year of publication

eg: (Assassin's Creed 3 2012)

Then you would create a reference list entry based on this format

Title year, video game, publisher, place.

Assassin's Creed 3 2012, video game, Ubisoft, London. 

Hope this helps,

David @ UTS Library