@misc{indiciae12b56538f1b4,
  title = {Solar polar coronal hole - A mathematical simulation},
  author = {Suess, S. T. and Richter, A. K. and Winge, C. R. and Nerney, S. F.},
  year = {1977},
  url = {https://ntrs.nasa.gov/citations/19770067733},
  note = {Source identifier: 19770067733}
}