Egri-Nagy, Attila (2011) "How to solve it?" - The tsumego session Annales Mathematicae et Informaticae. 38. pp. 137-145. ISSN 1787-5021 (Print), 1787-6117 (Online)
Egri-Nagy, Attila, Nehaniv, Chrystopher L. (2010) On the skeleton of a finite transformation semigroup Annales Mathematicae et Informaticae. 37. pp. 77-84. ISSN 1787-5021 (Print), 1787-6117 (Online)