@misc{indiciae3a9230864260,
  title = {Prebiotic 5-substituted uracils and a primitive genetic code.},
  author = {S Black},
  year = {1995},
  doi = {10.1126/science.7677859},
  url = {https://pubmed.ncbi.nlm.nih.gov/7677859/},
  note = {Source identifier: 7677859}
}