@article{MAN_1993__297_3_165153,
     author = {Michael Voit},
     title = {A positivity result and normalization of positive convolution structures.},
     journal = {Mathematische Annalen},
     pages = {677--692},
     publisher = {mathdoc},
     volume = {297},
     number = {3},
     year = {1993},
     zbl = {0856.43004},
     url = {http://geodesic.mathdoc.fr/item/MAN_1993__297_3_165153/}
}