@misc{indiciaef12360727538,
  title = {Porpoising behavior of penguins: energy conservation or respiratory necessity?},
  author = {Clifford A. Hui},
  year = {1987},
  doi = {10.1139/z87-031},
  url = {https://pubs.usgs.gov/publication/1007763},
  note = {Source identifier: 1007763}
}