https://ntrs.nasa.gov/api/citations/20190000915/downloads/20190000915.pdf
Authors. Fearn, Hudson, Eubanks, Long, Rodal, March, Woodward & van Rossum
Venue. NASA NIAC Phase I final report (NTRS 20190000915) (the grantees reporting their own results, including against themselves)
How the Institute flags it
frontier 1 time established 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.