@article{AFM_1982_7_2_a2,
     author = {Brad Beaver and Leo Sario and Cecilia Wang},
     title = {Positive biharmonic functions},
     journal = {Annales Fennici Mathematici},
     pages = {141--146},
     year = {1982},
     volume = {7},
     number = {2},
     doi = {10.5186/aasfm.1982.0714},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.5186/aasfm.1982.0714/}
}