@article{JLT_1991_1_2_a8,
     author = {A. May},
     title = {On a {Semigroup} in the {Work} of {Charles} {Loewner}},
     journal = {Journal of Lie theory},
     pages = {193--204},
     year = {1991},
     volume = {1},
     number = {2},
     url = {http://geodesic.mathdoc.fr/item/JLT_1991_1_2_a8/}
}