| APA | GLS. (2012, February 14). In Acronym Geek. Retrieved 10:08, February 14, 2012, from http://www.acronymgeek.com/GLS |
| MLA | "GLS." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/GLS>. |
| MHRA | 'GLS', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/GLS> [accessed 14 February 2012] |
| Chicago | "GLS", http://www.acronymgeek.com/GLS (accessed February 14, 2012). |
| CBE/CSE | GLS [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/GLS. |
| Bluebook | GLS, http://www.acronymgeek.com/GLS (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, GLS, http://www.acronymgeek.com/GLS (optional description here) (as of Feb. 14, 2012, 10:08). |
| AMA | GLS. Acronym Geek. February 14, 2012, 10:08. Available at: http://www.acronymgeek.com/GLS. Accessed February 14, 2012, 10:08. |