https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1536925
Authors. Elkins, Z., Ginsburg, T. & Melton, J
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.