Evaluation of the contents of selected heavy metals in organs of willow {\em(salix viminalis)} as a measure of its potential use for sewage sludge utilization / B. Różanowski, M. MICHAŁOWSKI // W: Effects on organisms and environment : III conference on Trace metals : Sopot, 6–8 June 2000 : book of abstracts / Institute of Oceanology PAS ; University of Gdańsk. — [Gdańsk : s. n.], 2000. — ISBN10: 83-911901-2-9. — S. 223/P2-50