@misc{indiciaefc41278cef2c,
  title = {Determination of prothrombin by a micro-coagulation method.},
  author = {B Kirchhof and S Schmale and J van de Loo},
  year = {1983},
  doi = {10.1159/000214697},
  url = {https://pubmed.ncbi.nlm.nih.gov/6840624/},
  note = {Source identifier: 6840624}
}