[4] Sucheston L.:
A note on conservative transformations and the recurrence theorem. Amer. J. Math. 79 (1957), 444-447.
MR 0085323 |
Zbl 0077.27002
[5] Tamm C. T.:
Recurrent properties of conservative measurable transformations. Dukе Math. J. 28 (1961), 277-279.
MR 0125936