@misc{indiciaedfe7463d0ba5,
  title = {Halos around planetary nebulae},
  author = {Jewitt, D. C. and Danielson, G. E. and Kupferman, P. N.},
  year = {1986},
  url = {https://ntrs.nasa.gov/citations/19860046710},
  note = {Source identifier: 19860046710}
}