Battery impedance and its relation to battery characteristicsTenno, Ander; Tenno, Robert; Suntio, TeuvoProc. 24th INTELEC Conf., Montreal, Canada, 20022002 / p. 176-183 https://www.researchgate.net/publication/3976210_Battery_impedance_and_its_relationship_to_battery_characteristics

The effects of intermittent charging on VRLA battery life expectancy in telecom applicationsSuntio, Teuvo; Waltari, P.; Tenno, Ander; Tenno, RobertProc. 24th INTELEC Conf., Montreal, Canada, 20022002 / p. 121-127