@article{mcdonald:1969:cem,
    author = {McDonald, F. A. and Nuttall, J.},
     title = {Complex-energy method for elastic $e$-{H} scattering above the
              ionization threshold},
   journal = {Phys. Rev. Lett.},
    volume = {23},
      year = {1969},
    number = {7},
     pages = {361–363},
       doi = {10.1103/PhysRevLett.23.361}}