@misc{indiciae3eab9f287760,
  title = {Spatial vectors and the angles they enclose.},
  author = {E J FISCHMANN},
  year = {1955},
  doi = {10.1136/hrt.17.4.496},
  url = {https://pubmed.ncbi.nlm.nih.gov/13269610/},
  note = {Source identifier: 13269610}
}