@misc{indiciaec8453da6e7eb,
  title = {Fifteenth breeding-bird census. 7. Virgin spruce-hemlock bog forest},
  author = {R. E. Stewart and C.S. Robbins},
  year = {1951},
  url = {https://pubs.usgs.gov/publication/5220107},
  note = {Source identifier: 5220107}
}