@article{ASENS_1979_4_12_1_33_0,
     author = {Nygaard, Niels O.},
     title = {Closedness of regular $1$-forms on algebraic surfaces},
     journal = {Annales scientifiques de l'\'Ecole Normale Sup\'erieure},
     pages = {33--45},
     publisher = {Elsevier},
     volume = {Ser. 4, 12},
     number = {1},
     year = {1979},
     doi = {10.24033/asens.1360},
     mrnumber = {80j:14019},
     zbl = {0428.14008},
     language = {en},
     url = {http://archive.numdam.org/articles/10.24033/asens.1360/}
}