Křesomysl Blizzard https://zbmath.org/authors/blizzard.kresomysl was a pseudonym of the collective of Walter Schachermayer, Erik G. F. Thomas and Heinrich von Weizsäcker for the publication
Blizzard, Křesomysl, A Krein-Milman set without the integral representation property., Frolík, Zdeněk (ed.), Abstracta. 8th winter school on abstract analysis. Abstracts of papers presented at the winter school, WSAA 8, Moravská Bouda, Czech Republic, 1980. Prague: Czechoslovak Academy of Sciences. 39-42 (1980). ZBL1437.46007.
Note that the DML CZ https://dml.cz/handle/10338.dmlcz/701173 did only partially resolve the identity as E.G.F. Thomas with the remark "Author corrected, K. Blizzard did not participated at the school"; the full identity is given in [20] of Schachermeyer's homepage https://www.mat.univie.ac.at/~schachermayer/pubs/index.php.