@article{noble:1984:cpe,
    author = {Noble, C. J. and Thompson, I. J.},
     title = {{COULN}, a program for evaluating negative energy
             {C}oulomb functions},
   journal = {Comput. Phys. Comm.},
  fjournal = {Computer Physics Communications},
    volume = {33},
      year = {1984},
    number = {4},
     pages = {413–419},
      note = {Double-precision Fortran code.},
       doi = {10.1016/0010-4655(84)90146-2},
     links = {\URL[Code]{http://cpc.cs.qub.ac.uk/summaries/ACCU}}}