@misc{indiciae4490c0604745,
  title = {Morphology and compositional differentiation of the surface of comets},
  author = {Huebner, W. F. and Boice, D. C.},
  year = {1989},
  url = {https://ntrs.nasa.gov/citations/19900007308},
  note = {Source identifier: 19900007308}
}