PIŠÚT, Ivan - PIŠÚT, Peter. Changes of epiphytic lichens in the surroundings of magnesite factories near Jelšava (SE Slovakia) in the period 1973-2004. In Ekológia : časopis pre ekologické problémy biosféry. - Bratislava : Academic electronic press, 2006. ISSN 1335-342X, 2006, vol. 25, no. 2, s. 176-187.