%0 Book part %D 1999 %G English %B Tiscia monograph series %B The Upper Tisa valley : preparatory proposal for Ramsar site designation and an ecological background Hungarian, Romanian, Slovakian and Ukrainian co-operation %@ 1418-0448 %T The Upper Tisa valley ecological background %U http://acta.bibl.u-szeged.hu/10197/1/tiscia_mono_004_125.pdf