Martin Grohe. The complexity of homomorphism and constraint satisfaction problems seen from the other side. Journal of the ACM, 54(1), 2007. [doi]
@article{Grohe07:1,
title = {The complexity of homomorphism and constraint satisfaction problems seen from the other side},
author = {Martin Grohe},
year = {2007},
doi = {10.1145/1206035.1206036},
url = {http://doi.acm.org/10.1145/1206035.1206036},
tags = {constraints},
researchr = {https://researchr.org/publication/Grohe07%3A1},
cites = {0},
citedby = {0},
journal = {Journal of the ACM},
volume = {54},
number = {1},
}