@article{10_37236_2606,
     author = {Federico Montecalvo},
     title = {Some constructions of general covering designs},
     journal = {The electronic journal of combinatorics},
     year = {2012},
     volume = {19},
     number = {3},
     doi = {10.37236/2606},
     zbl = {1253.05058},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/2606/}
}