@misc{indiciae2a69ff566ec4,
  title = {Differential changes in the onset of spring across US National Wildlife Refuges and North American migratory bird flyways},
  author = {Eric K. Waller and Theresa M. Crimmins and Jessica J. Walker and Erin E. Posthumus and Jake Weltzin},
  year = {2018},
  doi = {10.1371/journal.pone.0202495},
  url = {https://pubs.usgs.gov/publication/70199254},
  note = {Source identifier: 70199254}
}