@misc{indiciae957a87639bfd,
  title = {Rare earths, other trace elements and iron in Luna 20 samples.},
  author = {Helmke, P. A. and Blanchard, D. P. and Jacobs, J. W. and Haskin, L. and Haskin, A.},
  year = {1973},
  url = {https://ntrs.nasa.gov/citations/19730043515},
  note = {Source identifier: 19730043515}
}