@article{DMTCS_2018_19_2_a4,
     author = {Sliacan, Jakub and Stromquist, Walter},
     title = {Improving bounds on packing densities of 4-point permutations},
     journal = {Discrete mathematics & theoretical computer science},
     publisher = {mathdoc},
     volume = {19},
     number = {2},
     year = {2017-2018},
     doi = {10.23638/DMTCS-19-2-3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.23638/DMTCS-19-2-3/}
}