@misc{indiciae8ba6c2effb28,
  title = {Simplified model for positronium-helium scattering},
  author = {Drachman, R. J. and Houston, S. K.},
  year = {1970},
  url = {https://ntrs.nasa.gov/citations/19700021518},
  note = {Source identifier: 19700021518}
}