| APA | PTGI. (2012, February 16). In Acronym Geek. Retrieved 06:52, February 16, 2012, from http://www.acronymgeek.com/PTGI |
| MLA | "PTGI." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/PTGI>. |
| MHRA | 'PTGI', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/PTGI> [accessed 16 February 2012] |
| Chicago | "PTGI", http://www.acronymgeek.com/PTGI (accessed February 16, 2012). |
| CBE/CSE | PTGI [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/PTGI. |
| Bluebook | PTGI, http://www.acronymgeek.com/PTGI (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PTGI, http://www.acronymgeek.com/PTGI (optional description here) (as of Feb. 16, 2012, 06:52). |
| AMA | PTGI. Acronym Geek. February 16, 2012, 06:52. Available at: http://www.acronymgeek.com/PTGI. Accessed February 16, 2012, 06:52. |