@article{MAN_1965__162_161344,
     author = {J. NIETO},
     title = {Variations on a {Theme} by {Mikhlin.}},
     journal = {Mathematische Annalen},
     pages = {331--336},
     publisher = {mathdoc},
     volume = {162},
     year = {1965},
     zbl = {0128.33501},
     url = {http://geodesic.mathdoc.fr/item/MAN_1965__162_161344/}
}