@misc{indiciae620190a4dcc6,
  title = {A laboratory program to develop improved grazing incidence X-ray optics},
  author = {Giacconi, R. and Haggerty, R. and Reidy, W. and Vaiana, G. and Zehnpfennig, T.},
  year = {1967},
  url = {https://ntrs.nasa.gov/citations/19670008831},
  note = {Source identifier: 19670008831}
}