Miklós Ajtai Generalizations of the Compactness Theorem and Gödel's Completeness Theorem for Nonstandard Finite Structures. 13-33 2007 conf/tamc/2007 TAMC http://dx.doi.org/10.1007/978-3-540-72504-6_2 db/conf/tamc/tamc2007.html#Ajtai07