@misc{indiciae8ca7e18483d0,
  title = {Flight crew sleep during multiple layover polar flights},
  author = {Sasaki, Mitsuo and Kurosaki, Yuko S. and Spinweber, Cheryl L. and Graeber, R. C. and Takahashi, Toshiharu},
  year = {1993},
  url = {https://ntrs.nasa.gov/citations/19930065229},
  note = {Source identifier: 19930065229}
}