@article{MZ_1976__151_172432,
     author = {J\"urgen Bliedtner and Wolfhard Hansen},
     title = {Cones of {Hyperharmonic} {Functions.}},
     journal = {Mathematische Zeitschrift},
     pages = {71--88},
     publisher = {mathdoc},
     volume = {151},
     year = {1976},
     zbl = {0319.31011},
     url = {http://geodesic.mathdoc.fr/item/MZ_1976__151_172432/}
}