
A1: Modelling the Combination of Functional and Logic Programming Languages. Journal of Symbolic Computation 2, 123-138: 1986 (together with U. Furbach).
A2: The Undecidability of the Unification and Matching Problem for Canonical Theories. Acta Informatica 24, 157-171: 1987 (together with S. Heilbrunner).
A3: Horn Equality Theories and Paramodulation. Journal of Automated Reasoning 5, 309-337: 1989 (together with U. Furbach and J. Schreiber).
A4: Conditional Equational Theories and Complete Sets of Transformations. Theoretical Computer Science 75, 85-110: 1990.
A5: A New Approach to Deductive Planning. New Generation Computing 8, 225-244: 1990 (together with J. Schneeberger).
A6: Combining Logic Programming and Equation Solving. Journal of Logic and Computation 1, 397-415: 1991.
A7: On the Artificial Intelligence Paradox. Journal of Behavioral and Brain Sciences: 16, 463-464: 1993.
A8: Computing Change and Specificity with Equational Logic Programs. Annals of Mathematics and Artificial Intelligence 14, 99-133: 1995 (together with M. Thielscher).
A9: Deduktives Planen. Wissenschaftliche Zeitschrift der TU Dresden: 44, 29-44: 1996 (together with S.-E. Bornscheuer).
A10: Linear Deductive Planning. Journal of Logic and Computation: 6(2), 233-262: 1996 (together with G. Große and J. Schneeberger).
A11: Approximating the Semantics of Logic Programs by Recurrent Neural Networks. Applied Intelligence 11, 45-58: 1999 (together with Y. Kalinke and H.-P. Störr).
A12: The Fuzzy Description Logic ALC_FH with Hedge Algebras as Concept Modifiers. International Journal of Advanced Computational Intelligence and Intelligent Informatics 7, 294-305: 2003 (together with H.-P. Störr and Tran Dinh Khang).
A13: Logic Programs and Connectionist Networks. Journal of Applied Logic 2, 245-272: 2004 (together with P. Hitzler and A.K. Seda).
A14: The Integration of Connectionsim and First-Order Knowledge Representation and Reasoning as a Challenge for Artificial Intelligence. Information 9, 7-20: 2006 (together with S. Bader and P. Hitzler).
A15: FLUCAP: A Heuristic Search Planner for First-Order MDPs. Journal of Artificial Intelligence Research: 27: 419-439: 2006 (together with E. Karabaev and O. Skvortsova).
A16: Connectionist Model Generation: A First-Order Approach. Neurocomputing (to appear): 2008 (together with S. Bader and P. Hitzler).