@article{IM_1984__78_143178,
     author = {G. W\"ustholz},
     title = {Zum {Periodenproblem.}},
     journal = {Inventiones mathematicae},
     pages = {381--392},
     year = {1984},
     volume = {78},
     url = {http://geodesic.mathdoc.fr/item/IM_1984__78_143178/}
}