| APA | OPVL. (2012, February 16). In Acronym Geek. Retrieved 04:56, February 16, 2012, from http://www.acronymgeek.com/OPVL |
| MLA | "OPVL." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/OPVL>. |
| MHRA | 'OPVL', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/OPVL> [accessed 16 February 2012] |
| Chicago | "OPVL", http://www.acronymgeek.com/OPVL (accessed February 16, 2012). |
| CBE/CSE | OPVL [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/OPVL. |
| Bluebook | OPVL, http://www.acronymgeek.com/OPVL (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OPVL, http://www.acronymgeek.com/OPVL (optional description here) (as of Feb. 16, 2012, 04:56). |
| AMA | OPVL. Acronym Geek. February 16, 2012, 04:56. Available at: http://www.acronymgeek.com/OPVL. Accessed February 16, 2012, 04:56. |