@misc{indiciae67220c1b75fc,
  title = {Apsidal advance in Vela X-1},
  author = {Deeter, J. E. and Boynton, P. E. and Lamb, F. K. and Zylstra, G.},
  year = {1987},
  url = {https://ntrs.nasa.gov/citations/19870049395},
  note = {Source identifier: 19870049395}
}