@article{GDZPPN002033283, title = {Finite return times for measure-preserving transformations.}, journal = {Aequationes mathematicae}, volume = {22}, year = {1981}, pages = {24-29}, zbl = {0496.28018}, url = {http://dml.mathdoc.fr/item/GDZPPN002033283} }
Clark, Jack; David, Karl. Finite return times for measure-preserving transformations.. Aequationes mathematicae, Tome 22 (1981) pp. 24-29. http://gdmltest.u-ga.fr/item/GDZPPN002033283/