@article{10_1017_S001708950000803X,
     author = {Droste, Manfred and Shortt, R. M.},
     title = {Commutators in groups of order-preserving permutations},
     journal = {Glasgow mathematical journal},
     pages = {55--59},
     year = {1991},
     volume = {33},
     number = {1},
     doi = {10.1017/S001708950000803X},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S001708950000803X/}
}