Hvornår var sidste gang der var surt regn?
Acid rain
Likens, G. E.; Bormann, F. H. (1974). "Acid Rain: A Serious Regional Environmental Problem". Science. 184 (4142): 1176-9. Bibcode:1974Sci...184.1176L. doi:10.1126/science.184.4142.1176. PMID 17756304.
Acid rain
Likens, G. E.; Bormann, F. H. (1974). "Acid Rain: A Serious Regional Environmental Problem". Science. 184 (4142): 1176–9. Bibcode:1974Sci...184.1176L. doi:10.1126/science.184.4142.1176. PMID 17756304.
Acid rain