@inproceedings{DBLP:conf/ecsqaru/BruningS99, title = {Avoiding Non-ground Variables}, author = {Br{\"{u}}ning, Stefan and Schaub, Torsten}, booktitle = {{ESCQARU}}, pages = {92--103}, publisher = {Springer}, series = {Lecture Notes in Computer Science}, volume = {1638}, year = {1999} }