| APA | GPXO. (2012, February 15). In Acronym Geek. Retrieved 00:37, February 15, 2012, from http://www.acronymgeek.com/GPXO |
| MLA | "GPXO." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/GPXO>. |
| MHRA | 'GPXO', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/GPXO> [accessed 15 February 2012] |
| Chicago | "GPXO", http://www.acronymgeek.com/GPXO (accessed February 15, 2012). |
| CBE/CSE | GPXO [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/GPXO. |
| Bluebook | GPXO, http://www.acronymgeek.com/GPXO (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, GPXO, http://www.acronymgeek.com/GPXO (optional description here) (as of Feb. 15, 2012, 00:37). |
| AMA | GPXO. Acronym Geek. February 15, 2012, 00:37. Available at: http://www.acronymgeek.com/GPXO. Accessed February 15, 2012, 00:37. |