Cross-Platform, Cross-Grammar Comparison - Can it be Done? - Ulrich Callmeier; Stephan Oepen (ELSPS, 2000)

Measure for Measure: Parser Cross-fertilization - Towards Increased Component Comparability and Exchange. - Stephan Oepen; Ulrich Callmeier (IWPT, 2000)

PET - a platform for experimentation with efficient HPSG processing techniques. - Ulrich Callmeier (Nat. Lang. Eng., 2000)

The DeepThought Core Architecture Framework. - Ulrich Callmeier; Andreas Eisele 001; Ulrich Schäfer 001; Melanie Siegel (LREC, 2004)

Some Fine Points of Hybrid Natural Language Parsing. - Peter Adolphs; Stephan Oepen; Ulrich Callmeier; Berthold Crysmann; Dan Flickinger; Bernd Kiefer (LREC, 2008)