@article{EXMA_2005__14_3_52335,
     author = {Nickerson, S.J. and Wilson, R.A.},
     title = {Semi-presentations for the sporadic simple groups.},
     journal = {Experimental mathematics},
     pages = {359--371},
     publisher = {mathdoc},
     volume = {14},
     number = {3},
     year = {2005},
     zbl = {1087.20025},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EXMA_2005__14_3_52335/}
}