Siegfried Gottwald “Mathematical Fuzzy Logics,” in: The Bulletin of Symbolic Logic, vol. 14, no. 2, 2008 Timothy Bays “Skolem's Paradox,” in: The Stanford Encyclopedia of Philosophy, January 12, 2009 PS 次の論文などを読んだりしておりました…

Petr Hájek Metamathematics of Fuzzy Logic, Springer, Trends in Logic, vol. 4, 2002