@article{10_37236_4548,
     author = {Tam\'as M\'esz\'aros and Lajos R\'onyai},
     title = {Shattering-extremal set systems of {VC} dimension at most 2},
     journal = {The electronic journal of combinatorics},
     year = {2014},
     volume = {21},
     number = {4},
     doi = {10.37236/4548},
     zbl = {1302.05201},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/4548/}
}