@phdthesis{THESE_1940__231__1_0,
     author = {Kuntzmann, J.},
     title = {Contribution \`a l'\'etude des syst\`emes multiformes},
     series = {Th\`eses de l'entre-deux-guerres},
     number = {231},
     year = {1940},
     language = {fr},
     url = {http://www.numdam.org/item/THESE_1940__231__1_0/}
}