@article{10_4153_CMB_1969_005_8,
     author = {Leech, John},
     title = {A {Presentation} of the {Mathieu} {Group} {M12}},
     journal = {Canadian mathematical bulletin},
     pages = {41--43},
     year = {1969},
     volume = {12},
     number = {1},
     doi = {10.4153/CMB-1969-005-8},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1969-005-8/}
}