@article{AFM_1966_371-390_a18,
     author = {Arne Beurling},
     title = {A minimum principle for positive harmonic functions},
     journal = {Annales Fennici Mathematici},
     publisher = {mathdoc},
     volume = {371-390},
     year = {1966},
     doi = {10.5186/aasfm.1966.372},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.5186/aasfm.1966.372/}
}