| APA | SPPO. (2012, February 12). In Acronym Geek. Retrieved 06:09, February 12, 2012, from http://www.acronymgeek.com/SPPO |
| MLA | "SPPO." Acronym Geek. (2012). Acronym Geek. 12 Feb 2012 <http://www.acronymgeek.com/SPPO>. |
| MHRA | 'SPPO', Acronym Geek, 12 February 2012, <http://www.acronymgeek.com/SPPO> [accessed 12 February 2012] |
| Chicago | "SPPO", http://www.acronymgeek.com/SPPO (accessed February 12, 2012). |
| CBE/CSE | SPPO [Internet]. Acronym Geek; 2012 Feb 12 [cited 2012 Feb 12]. Available from: http://www.acronymgeek.com/SPPO. |
| Bluebook | SPPO, http://www.acronymgeek.com/SPPO (last visited February 12, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, SPPO, http://www.acronymgeek.com/SPPO (optional description here) (as of Feb. 12, 2012, 06:09). |
| AMA | SPPO. Acronym Geek. February 12, 2012, 06:09. Available at: http://www.acronymgeek.com/SPPO. Accessed February 12, 2012, 06:09. |