@inproceedings{SAT-2006-KullmannLM,
	author        = "Oliver Kullmann and Inês Lynce and João Marques-Silva",
	booktitle     = "{Proceedings of the Ninth International Conference on Theory and Applications of Satisfiability Testing}",
	doi           = "10.1007/11814948_4",
	isbn          = "3-540-37206-7",
	pages         = "22--35",
	publisher     = "{Springer International Publishing}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Categorisation of Clauses in Conjunctive Normal Forms: Minimally Unsatisfiable Sub-clause-sets and the Lean Kernel}",
	volume        = 4121,
	year          = 2006,
}