citation-style-language/styles — pull request #739 by aurimasv (2013-11-03 23:36:23+00:00)
Title: [PNAS] Add thesis type.

As per https://forums.zotero.org/discussion/33024/pnas-citation-format/

Sample: reference 20 in http://doi.org/10.1073/pnas.1302295110