1. G. Hardy, Divergent Series, Oxford, 1949.
2. D. L. Hanson and G. Pledger, “On the mean ergodic theorem for weighted averages,” Z. Wahrscheinlichkeitstheorie Verw. Geb., 13 (1969), no. 13, 141–149.
3. V. V. Kozlov, “Summation of divergent series and ergodic theorems,” Trudy Sem. Petrovsk., 22 (2002), 142–168.
4. G. Baxter, “An ergodic theorem with weighted averages,” J. Math. Mech., 13 (1964), no. 3, 481–488.
5. R. V. Chacon, “Ordinary means imply recurrent means,” Bull. Amer. Math. Soc., 70 (1964), 796–797.