| APA | GCS. (2012, February 14). In Acronym Geek. Retrieved 09:57, February 14, 2012, from http://www.acronymgeek.com/GCS |
| MLA | "GCS." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/GCS>. |
| MHRA | 'GCS', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/GCS> [accessed 14 February 2012] |
| Chicago | "GCS", http://www.acronymgeek.com/GCS (accessed February 14, 2012). |
| CBE/CSE | GCS [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/GCS. |
| Bluebook | GCS, http://www.acronymgeek.com/GCS (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, GCS, http://www.acronymgeek.com/GCS (optional description here) (as of Feb. 14, 2012, 09:57). |
| AMA | GCS. Acronym Geek. February 14, 2012, 09:57. Available at: http://www.acronymgeek.com/GCS. Accessed February 14, 2012, 09:57. |