• Corroded hydrothermal quartz in Ordovician altered volcanic ash beds of the Baltoscandian RegionKiipli, Tarmo; Kallaste, Toivo; Kleesment, Anne-Liis; Nielsen, Arne T.Estonian journal of earth sciences2009 / 4, p. 268-272 : ill https://artiklid.elnet.ee/record=b1944231*est