@book{ Solr-acta10221, title = {Birds of the Ukrainian region of the Upper Tisa}, series = {Tiscia monograph series}, series = {The Upper Tisa valley : preparatory proposal for Ramsar site designation and an ecological background Hungarian, Romanian, Slovakian and Ukrainian co-operation}, author = {Potish Ludvik}, year = {1999}, url = {http://acta.bibl.u-szeged.hu/10221/1/tiscia_mono_004_481-487.pdf} }