@article{AIF_1993__43_2_301_0,
     author = {Gouv\^ea, Fernando Q. and Mazur, Barry},
     title = {On the characteristic power series of the {U} operator},
     journal = {Annales de l'Institut Fourier},
     pages = {301--312},
     publisher = {Institut Fourier},
     address = {Grenoble},
     volume = {43},
     number = {2},
     year = {1993},
     doi = {10.5802/aif.1332},
     zbl = {0779.11022},
     mrnumber = {1220270},
     language = {en},
     url = {http://www.numdam.org/articles/10.5802/aif.1332/}
}