Litak, T. and Mikulás, Szabolcs and Hidders, Jan (2016) Relational lattices: from databases to Universal Algebra. Journal of Logical and Algebraic Methods in Programming 85 (4), pp. 540-573. ISSN 2352-2208.

ten Cate, B. and Litak, T. and Marx, M. (2010) Complete axiomatizations for XPath fragments. Journal of Applied Logic 8 (2), pp. 153-172. ISSN 1570-8683.

Litak, T. and Helmer, Sven (2009) On the termination problem for declarative xml message processing. In: Bhowmick, S.S. and Küng, J. and Wagner, R. (eds.) Database and Expert Systems Applications. Berlin, Germany: Springer Verlag, pp. 83-97. ISBN 9783642035739.