@article{JIS_2015__18_6_a1,
     author = {Gent,  Ian and Kitaev,  Sergey and Konovalov,  Alexander and Linton,  Steve and Nightingale,  Peter},
     title = {\(S\)-crucial and bicrucial permutations with respect to squares},
     journal = {Journal of integer sequences},
     year = {2015},
     volume = {18},
     number = {6},
     zbl = {1327.05005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2015__18_6_a1/}
}