@misc{indiciae34c9d138958c,
  title = {Secular variations of L, B-coordinates},
  author = {Getselev, I. V. and Gorchakov, E. V. and Eltekov, V. A.},
  year = {1975},
  url = {https://ntrs.nasa.gov/citations/19750008393},
  note = {Source identifier: 19750008393}
}