https://www.nature.com/articles/s41591-020-0942-0
Authors. Tschandl, Rinner, Apalla et al
Venue. Nature Medicine
How the Institute flags it
established 2 times frontier 1 time
This source carries more than one flag across the corpus. That is not an inconsistency to resolve: the same work can be established evidence for one claim and frontier evidence for another, and the flag belongs to the use rather than to the source.