| APA | GRCK. (2012, February 15). In Acronym Geek. Retrieved 11:37, February 15, 2012, from http://www.acronymgeek.com/GRCK |
| MLA | "GRCK." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/GRCK>. |
| MHRA | 'GRCK', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/GRCK> [accessed 15 February 2012] |
| Chicago | "GRCK", http://www.acronymgeek.com/GRCK (accessed February 15, 2012). |
| CBE/CSE | GRCK [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/GRCK. |
| Bluebook | GRCK, http://www.acronymgeek.com/GRCK (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, GRCK, http://www.acronymgeek.com/GRCK (optional description here) (as of Feb. 15, 2012, 11:37). |
| AMA | GRCK. Acronym Geek. February 15, 2012, 11:37. Available at: http://www.acronymgeek.com/GRCK. Accessed February 15, 2012, 11:37. |