• Rare metals in volcanic ash beds in Silurian sedimentary sections of Estonia, Ukraine and Moldova - application for correlations between regionsKiipli, Tarmo; Tsegelnjuk, PetroRare metals in Ukraine - view to the future : conference materials : June 18.-22. 2001 : Kyev, Inst. Geol. Acad. Sci. Ukraine2001 / p. 59-61