Citing The IUCN Red List of Threatened Species as a Whole:
To cite The IUCN Red List of Threatened Species in general, users are advised to follow the format suggested below, changing the dates and version numbers as appropriate.
Within the text use "...IUCN (2015)..." or "...(IUCN 2015)...".
In a bibliography or reference list, the above would be cited in full as follows:
IUCN 2015. The IUCN Red List of Threatened Species. Version 2015-4. <http://www.iucnredlist.org>. Downloaded on 19 November 2015.
Citing Specific Assessments:
In citing specific assesments, users are advised to note that we are in the middle of a process to make all assesments published on The IUCN Red List available as downloadable PDF documents with DOIs so that they will be permanently retrievable. Hence while this process is underway, the full citation format will differ slightly between assesments with PDFs and DOIs and those without.
To cite specific assessments in the text use the authors of the assessment and the date the assessment was published (for these details, see the preferred citation at the bottom of the relevant 'species' fact sheet). So for example in referring to the assessment of Zaglossus bruijnii (see http://www.iucnredlist.org/details/23179/0) this would be cited as "....Leary et al. (2008)..." or "...(Leary et al. 2008)...."
To cite a specific asessment users are asked to treat it in the same way as they would a paper in an online scientific journal. The preferred citation appears at the bottom of the 'species' fact sheet. This generally uses the Assessor(s) name(s) as the author(s), the date the assessment was published, the name of the taxon and then the The IUCN Red List of Threatened Species as the journal title followed by the year as the volume number.
Examples of citations for assessments without PDFs and DOIs:
Lafrance, P., Lourie, S., Marsden, D. and Vincent, A.C.J. 2002. Hippocampus subelongatus. The IUCN Red List of Threatened Species 2002: e.T40773A10352905. Downloaded on 19 November 2015.
Leary, T., Seri. L., Flannery, T., Wright, D., Hamilton, S., Helgen, K., Singadan, R., Menzies, J., Allison, A., James, R., Aplin, K., Salas, L. and Dickman, C. 2008. Zaglossus bruijnii. The IUCN Red List of Threatened Species 2008: e.T23179A9426076. Downloaded on 19 November 2015.
Examples of citations for assessments with PDFs and DOIs [note that the DOI in the first example includes the particular version in 2014 i.e. "2014-2"]:
BirdLife International. 2014. Gyps coprotheres. The IUCN Red List of Threatened Species 2014: e.T22695225A62502298. http://dx.doi.org/10.2305/IUCN.UK.2014-2.RLTS.T22695225A62502298.en. Downloaded on 9 September 2015.
Blanc, J. 2008. Loxodonta africana. The IUCN Red List of Threatened Species 2008: e.T12392A3339343. http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T12392A3339343.en. Downloaded on 19 November 2015.