I'm looking for a PDF copy of Blass's 1970 Harvard Thesis "Orderings of ultrafilters". When I search for it online, I find many references to it, but I cannot find a hosting of a scanned PDF. I did have one at one point, but the link stopped working, and archive.org did not archive it.
The following is the full citation I originally followed:
Andreas Raphael Blass, Orderings of ultrafilters, ProQuest LLC, Ann Arbor, MI, 1970. Thesis (Ph.D.)–Harvard University. MR2939947