@misc{indiciae22b373b38ee3,
  title = {Subspace Hamiltonian technique.},
  author = {RE Allen and M Menon},
  year = {1986},
  doi = {10.1103/physrevb.33.5611},
  url = {https://pubmed.ncbi.nlm.nih.gov/9939070/},
  note = {Source identifier: 9939070}
}