1. Lecture Notes in Artificial Intelligence;P. Blache,2005
2. Boyd, A.A.: Detecting and diagnosing grammatical errors for beginning learners of german: From learner corpus annotation to constraint satisfaction problems. Ph.D. thesis, Ohio State University (2012)
3. Brown, H.: Principles of learning and teaching. White Plans, New York (2000)
4. Chomsky, N.: Syntactic Structures. Mouton, The Hague (1957)
5. Christiansen, H.: CHR grammars. TPLP 5(4-5), 467–501 (2005)