| APA | GPYI. (2012, February 15). In Acronym Geek. Retrieved 20:28, February 15, 2012, from http://www.acronymgeek.com/GPYI |
| MLA | "GPYI." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/GPYI>. |
| MHRA | 'GPYI', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/GPYI> [accessed 15 February 2012] |
| Chicago | "GPYI", http://www.acronymgeek.com/GPYI (accessed February 15, 2012). |
| CBE/CSE | GPYI [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/GPYI. |
| Bluebook | GPYI, http://www.acronymgeek.com/GPYI (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, GPYI, http://www.acronymgeek.com/GPYI (optional description here) (as of Feb. 15, 2012, 20:28). |
| AMA | GPYI. Acronym Geek. February 15, 2012, 20:28. Available at: http://www.acronymgeek.com/GPYI. Accessed February 15, 2012, 20:28. |