| APA | NPDL. (2012, February 17). In Acronym Geek. Retrieved 05:53, February 17, 2012, from http://www.acronymgeek.com/NPDL |
| MLA | "NPDL." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/NPDL>. |
| MHRA | 'NPDL', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/NPDL> [accessed 17 February 2012] |
| Chicago | "NPDL", http://www.acronymgeek.com/NPDL (accessed February 17, 2012). |
| CBE/CSE | NPDL [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/NPDL. |
| Bluebook | NPDL, http://www.acronymgeek.com/NPDL (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, NPDL, http://www.acronymgeek.com/NPDL (optional description here) (as of Feb. 17, 2012, 05:53). |
| AMA | NPDL. Acronym Geek. February 17, 2012, 05:53. Available at: http://www.acronymgeek.com/NPDL. Accessed February 17, 2012, 05:53. |