@article{44751,
  author = {Lars Hedin and Gene Likens and Herbert Bormann},
  title = {Decrease in precipitation acidity resulting from decreased SO2- 4 concentration},
  year = {1987},
  journal = {Nature},
  volume = {325},
  number = {6101},
  pages = {244{\textendash}246},
  url = {http://www.nature.com/nature/journal/v325/n6101/abs/325244a0.html},
  language = {eng},
}