@article{SF_1993__47_2_135273,
     author = {C. Lizama},
     title = {A mean ergodic theorem for resolvent operators.},
     journal = {Semigroup forum},
     pages = {227--230},
     publisher = {mathdoc},
     volume = {47},
     number = {2},
     year = {1993},
     zbl = {0799.47024},
     url = {http://geodesic.mathdoc.fr/item/SF_1993__47_2_135273/}
}