@misc{indiciae319a455b7ed4,
  title = {Vertex operators for closed strings.},
  author = {E D'Hoker and DH Phong},
  year = {1987},
  doi = {10.1103/physrevd.35.3890},
  url = {https://pubmed.ncbi.nlm.nih.gov/9957651/},
  note = {Source identifier: 9957651}
}