Department of Environmental Engineering2001 https://www.ester.ee/record=b1236017*est Department of Environmental EngineeringVelner, Harald-Adam; Paal, Leopold; Mölder, Heino; Marvet, Rein; Kõiv, Teet-Andrus; Velner, Harald-AdamResearch activities / Tallinn Technical University1993 / p. 56-59 https://www.ester.ee/record=b1053754*est