@article{MSH_1969__27__21_0,
     author = {Lerman, I. C.},
     title = {H-classificabilit\'e},
     journal = {Math\'ematiques et sciences humaines},
     pages = {21--28},
     publisher = {Ecole Pratique des hautes \'etudes, Centre de math\'ematique sociale et de statistique},
     volume = {27},
     year = {1969},
     language = {fr},
     url = {http://www.numdam.org/item/MSH_1969__27__21_0/}
}