@article{ASCFM_1981__69_19_P5_0,
     title = {Introduction},
     journal = {Annales scientifiques de l'Universit\'e de Clermont. Math\'ematiques},
     publisher = {UER de Sciences exactes et naturelles de l'Universit\'e de Clermont},
     volume = {69},
     number = {19},
     year = {1981},
     pages = {5-5},
     language = {fr},
     url = {http://www.numdam.org/item/ASCFM_1981__69_19_P5_0}
}