@article{DMGAA_2009_29_2_a1,
     author = {Couceiro, Miguel and Foldes, Stephan},
     title = {Function classes and relational constraints stable under compositions with clones},
     journal = {Discussiones Mathematicae. General Algebra and Applications},
     pages = {109--121},
     publisher = {mathdoc},
     volume = {29},
     number = {2},
     year = {2009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGAA_2009_29_2_a1/}
}