From Safer nicotine wiki
- lay-url: URL link to a non-technical summary or review of the source; the URL title is set to "Lay summary".
- lay-source: Name of the source of the lay summary. Displays in italics and preceded by a spaced endash.
- lay-date: Date of the lay summary. Displays in parentheses.
- lay-format: File format of the work referred to by lay-url; for example: PDF, DOC, or XLS; displayed in parentheses after lay summary. HTML is implied and should not be specified. File format annotation is automatically rendered when a PDF icon is displayed. Does not change the external link icon. Note: External link icons do not include alt text; thus, they do not add file format information for the visually impaired.