@article{JAC_2016__43_4_a1,
     author = {Roberson, David E.},
     title = {Conic formulations of graph homomorphisms},
     journal = {Journal of Algebraic Combinatorics},
     pages = {877--913},
     publisher = {mathdoc},
     volume = {43},
     number = {4},
     year = {2016},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JAC_2016__43_4_a1/}
}