Fomina, Lidiya S; Volkov, Igor I (1970): Rare earth elements in bottom sediments and Fe-Mn nodules of the Black Sea. P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, PANGAEA, https://doi.org/10.1594/PANGAEA.775793, Supplement to: Fomina, LS; Volkov, II (1970): Rare earth elements in sediments of the Black Sea. Litologiya i Poleznyye Iskopaemyye (Lithology and Mineral Resources), 5(2), 148-160