@misc{indiciaec1bf9ef2213a,
  title = {[Direct portography].},
  author = {K L Wiechel and K G Kulling and O Marions and R Erwald and K Lindberg},
  year = {1971},
  url = {https://pubmed.ncbi.nlm.nih.gov/5165721/},
  note = {Source identifier: 5165721}
}