Bārdule, A., Lazdiņa, D., Zadvinska, K., Buša, L., Vīksna, A. and Bārdulis, A. 2020. Carbon and nitrogen stabile isotope ratio and heavy metals in Leccinum aurantiacum in a hybrid aspen plantation in agricultural land initially fertilised with biogas production residues, sewage sludge, and wood ash. Baltic Forestry. 26, 1 (Mar. 2020). DOI:https://doi.org/10.46490/BF424.