Zigmontienė, Aušra, and Indrė Liberytė. “Changes in the Concentration of Heavy Metals (Cr, Cd, Ni) During the Vermicomposting Process of Sewage Sludge”. Mokslas – Lietuvos Ateitis Science – Future of Lithuania, vol. 6, no. 4, Oct. 2014, pp. 362-7, https://doi.org/10.3846/mla.2014.49.