Existential MSO over two successors is strictly weaker than over linear orders. - Christian Mathissen (Theor. Comput. Sci., 2009)

Weighted Automata and Weighted Logics over Tree-like Structures. - Christian Mathissen (2009)

Compressed Conjugacy and the Word Problem for Outer Automorphism Groups of Graph Groups. - Niko Haubold; Markus Lohrey; Christian Mathissen (Developments in Language Theory, 2010)

Weighted Logics for Nested Words and Algebraic Formal Power Series - Christian Mathissen (Log. Methods Comput. Sci., 2010)

Definable transductions and weighted logics for texts. - Christian Mathissen (Theor. Comput. Sci., 2010)

Rational Transformations and a Kleene Theorem for Power Series over Rational Monoids. - Ina Fichtner; Christian Mathissen (Algebraic Foundations in Computer Science, 2011)

Compressed Membership in Automata with Compressed Labels. - Markus Lohrey; Christian Mathissen (CSR, 2011)

Compressed Decision Problems for Graph Products and Applications to (outer) Automorphism Groups. - Niko Haubold; Markus Lohrey; Christian Mathissen (Int. J. Algebra Comput., 2012)

Isomorphism of regular trees and words. - Markus Lohrey; Christian Mathissen (Inf. Comput., 2013)