@misc{indiciae9a6725a57ca4,
  title = {Covariants of Binary Modular Groups.},
  author = {O E Glenn},
  year = {1919},
  doi = {10.1073/pnas.5.4.107},
  url = {https://pubmed.ncbi.nlm.nih.gov/16576354/},
  note = {Source identifier: 16576354}
}