@misc{indiciae2c46d1674750,
  title = {Opening the cusp},
  author = {Crooker, N. U. and Toffoletto, F. R. and Gussenhoven, M. S.},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910043358},
  note = {Source identifier: 19910043358}
}