@misc{indiciaec6917bdbb317,
  title = {Singularities in correlation functions for systems with defect lines and walls.},
  author = {PJ Upton},
  year = {1991},
  doi = {10.1103/physrevb.44.10335},
  url = {https://pubmed.ncbi.nlm.nih.gov/9999041/},
  note = {Source identifier: 9999041}
}