@misc{indiciae1294ad1b1e70,
  title = {Conservation sum rules for the quadratic density response function.},
  author = {ZC Tao and G Kalman},
  year = {1990},
  doi = {10.1103/physreva.42.6201},
  url = {https://pubmed.ncbi.nlm.nih.gov/9903903/},
  note = {Source identifier: 9903903}
}