| APA | PGOS. (2012, February 16). In Acronym Geek. Retrieved 04:45, February 16, 2012, from http://www.acronymgeek.com/PGOS |
| MLA | "PGOS." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/PGOS>. |
| MHRA | 'PGOS', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/PGOS> [accessed 16 February 2012] |
| Chicago | "PGOS", http://www.acronymgeek.com/PGOS (accessed February 16, 2012). |
| CBE/CSE | PGOS [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/PGOS. |
| Bluebook | PGOS, http://www.acronymgeek.com/PGOS (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PGOS, http://www.acronymgeek.com/PGOS (optional description here) (as of Feb. 16, 2012, 04:45). |
| AMA | PGOS. Acronym Geek. February 16, 2012, 04:45. Available at: http://www.acronymgeek.com/PGOS. Accessed February 16, 2012, 04:45. |