Twelve was first mentioned in Guide to the Grand Army of the Republic, an article written by Karen Traviss and Ryan Kaufman and published in Star Wars Insider 84 in September of 2005. In 2008, the clone trooper was mentioned in Hawkbat Battalion's entry in The Complete Star Wars Encyclopedia.
Twelve was first mentioned in Guide to the Grand Army of the Republic, an article written by Karen Traviss and Ryan Kaufman and published in Star Wars Insider 84 in September of 2005. In 2008, the clone trooper was mentioned in Hawkbat Battalion's entry in The Complete Star Wars Encyclopedia.
- "Guide to the Grand Army of the Republic" — Star Wars Insider 84
- The Complete Star Wars Encyclopedia, Vol. II