@misc{indiciae60b4f21d0cd5,
  title = {NGC7009: Testing the Wind-Wind Interaction Formation of Planetary Nebulae},
  author = {Chu, You-Hua and Gruendl, Robert and Guerrero, Martin},
  year = {2003},
  url = {https://ntrs.nasa.gov/citations/20040004350},
  note = {Source identifier: 20040004350}
}