@misc{indiciaebf4c19b28bea,
  title = {Multipair excitations and sum rules in interacting-electron systems.},
  author = {F Green and D Neilson and D Pines and J Szymanski},
  year = {1987},
  doi = {10.1103/physrevb.35.133},
  url = {https://pubmed.ncbi.nlm.nih.gov/9940579/},
  note = {Source identifier: 9940579}
}