@article{FladFladHarutyunyanSchulze2020,
  author    = {Heinz-J{\"u}rgen Flad and Gohar Flad-Harutyunyan and Bert-Wolfgang Schulze},
  title     = {Explicit Green operators for quantum mechanical Hamiltonians},
  journal   = {Asian-European journal of mathematics : AEJM},
  series    = {II. edge-type singularities of the helium atom},
  volume    = {13},
  number    = {7},
  doi       = {10.1142/S1793557120501223},
  year      = {2020},
}