• Chemical peculiarities of the Silurian-Ordovician and Cambrian-Vendian aquifer systems in Estonia : an overview of hydrochemical studiesKarro, Enn; Marandi, Andres; Vaikmäe, Rein; Uppin, MargeEstonian journal of earth sciences2009 / 4, p. 342-352 : ill https://artiklid.elnet.ee/record=b1944680*est