@article{Or³owski:2013,
  author  = "G. Or³owski and J. Karg",
  title   = "Diet breadth and overlap in three sympatric aerial insectivorous birds at the same location",
  journal = "Bird Study",
  volume  = "Vol. 60",
  pages   = "475--483",
  year    = "2013",
  note    = "podwójna afiliacja: J. Karg",
}