@article{Szeider03e,
 author = {Stefan Szeider},
 gsid = {https://scholar.google.com/scholar?oi=bibs&hl=en&cites=7861797934713042323,17346203107635875456&as_sdt=5},
 journal = {Discr. Appl. Math.},
 number = {2},
 pages = {351-365},
 title = {Homomorphisms of Conjunctive Normal Forms},
 url = {https://www.ac.tuwien.ac.at/files/pub/szeider-2003.pdf},
 volume = {130},
 year = {2003}
}