Definable Ultrapowers and the Omitting Types Theorem Žarko Mijajlović (1991) Publications de l'Institut Mathématique
Diassociativity is not finitely based relative to power associativity Tomasz Kowalski (2010) Commentationes Mathematicae Universitatis Carolinae We show that the variety of diassociative loops is not finitely based even relative to power associative loops with inverse property.