| APA | CPUO. (2012, February 16). In Acronym Geek. Retrieved 19:54, February 16, 2012, from http://www.acronymgeek.com/CPUO |
| MLA | "CPUO." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/CPUO>. |
| MHRA | 'CPUO', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/CPUO> [accessed 16 February 2012] |
| Chicago | "CPUO", http://www.acronymgeek.com/CPUO (accessed February 16, 2012). |
| CBE/CSE | CPUO [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/CPUO. |
| Bluebook | CPUO, http://www.acronymgeek.com/CPUO (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, CPUO, http://www.acronymgeek.com/CPUO (optional description here) (as of Feb. 16, 2012, 19:54). |
| AMA | CPUO. Acronym Geek. February 16, 2012, 19:54. Available at: http://www.acronymgeek.com/CPUO. Accessed February 16, 2012, 19:54. |