@article{SPS_1986__20__338_0,
     author = {Ruiz de Chavez, Juan},
     title = {Sur la positivit\'e de certains op\'erateurs},
     journal = {S\'eminaire de probabilit\'es de Strasbourg},
     pages = {338--340},
     publisher = {Springer - Lecture Notes in Mathematics},
     volume = {20},
     year = {1986},
     mrnumber = {942028},
     zbl = {0649.60074},
     language = {fr},
     url = {http://www.numdam.org/item/SPS_1986__20__338_0/}
}