@misc{indiciaeb01f27036ecb,
  title = {Visual observations of lunar libration center clouds},
  author = {Allen, W. H. and Krumm, W. J. and Randle, R. J.},
  year = {1967},
  url = {https://ntrs.nasa.gov/citations/19680018019},
  note = {Source identifier: 19680018019}
}