@article{MS2_1977__40_166536,
     author = {Bj\"orn E.J. Dahlberg},
     title = {On the radial boundary values of subharmonic functions.},
     journal = {Mathematica Scandinavica},
     pages = {301--317},
     year = {1977},
     volume = {40},
     zbl = {0371.31001},
     url = {http://geodesic.mathdoc.fr/item/MS2_1977__40_166536/}
}