From Safer nicotine wiki
- type: Provides additional information about the media type of the source. May alternatively be used to identify the type of manuscript linked to in the title, if this is not the final version of a manuscript (e.g. if a preprint of a manuscript is freely available, but the version of record is behind a paywall). Format in sentence case. Displays in parentheses following the title. The reserved keyword
nonecan be used to disable the display of a type. Examples: Thesis, Booklet, Accepted manuscript, CD liner, Press release. Alias: medium.