@misc{indiciaed24901e79930,
  title = {Absolute magnitude calibration using trigonometric parallax - Incomplete, spectroscopic samples},
  author = {Ratnatunga, Kavan U. and Casertano, Stefano},
  year = {1991},
  url = {https://ntrs.nasa.gov/citations/19910042706},
  note = {Source identifier: 19910042706}
}