@article{10_4064_sm_20_3_313_325,
     author = {S. Hartman},
     title = {\"Uber {Niveaulinien} fastperiodischer {Funktionen}},
     journal = {Studia Mathematica},
     pages = {313--325},
     year = {1961},
     volume = {20},
     number = {3},
     doi = {10.4064/sm-20-3-313-325},
     language = {de},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-20-3-313-325/}
}