@article{10_1090_S0894_0347_1993_1186960_7,
     author = {Harris, Michael},
     title = {\ensuremath{\mathit{L}}-functions of 2{\texttimes}2 unitary groups and factorization of periods of {Hilbert} modular forms},
     journal = {Journal of the American Mathematical Society},
     pages = {637--719},
     year = {1993},
     volume = {06},
     number = {3},
     doi = {10.1090/S0894-0347-1993-1186960-7},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-1993-1186960-7/}
}