@article{10_4153_CJM_1982_090_2,
     author = {Kieffer, John C. and Rahe, Maurice},
     title = {The {Pointwise} {Ergodic} {Theorem} for {Transformations} whose {Orbits} contain or are contained in the {Orbits} of a {Measure-Preserving} {Transformation}},
     journal = {Canadian journal of mathematics},
     pages = {1303--1318},
     year = {1982},
     volume = {34},
     number = {6},
     doi = {10.4153/CJM-1982-090-2},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1982-090-2/}
}