@inproceedings{Szeider01,
 author = {Stefan Szeider},
 booktitle = {IJCAR 2001, Proceedings of the International 
Joint Conference on Automated Reasoning},
 editor = {R. Gor\'{e} and A. Leitsch and T. Nipkow},
 pages = {168-181},
 publisher = {Springer Verlag},
 series = {Lecture Notes in Artificial Intelligence},
 title = {{NP}-Completeness of
Refutability by  Literal-Once Resolution},
 volume = {2083},
 year = {2001}
}