@misc{indiciae62a1c5649531,
  title = {Climate and reproduction of grizzly bears in Yellowstone National Park},
  author = {Harold D. Picton},
  year = {1978},
  doi = {10.1038/274888a0},
  url = {https://pubs.usgs.gov/publication/70169338},
  note = {Source identifier: 70169338}
}