@article{GDZPPN00242410X,
title = {Normal Subgroups of Triply Transitive Permutation Groups of Degree Divisible by 3.},
journal = {Mathematische Zeitschrift},
volume = {174},
year = {1980},
pages = {95-104},
zbl = {0423.20002},
url = {http://dml.mathdoc.fr/item/GDZPPN00242410X}
}
Siemons, Johannes. Normal Subgroups of Triply Transitive Permutation Groups of Degree Divisible by 3.. Mathematische Zeitschrift, Tome 174 (1980) pp. 95-104. http://gdmltest.u-ga.fr/item/GDZPPN00242410X/