@misc{indiciae54acaad2c605,
  title = {Outside Europe. Is poliomyelitis a serious problem in developing countries?--the Danfa experience.},
  author = {D D Nicholas and J H Kratzer and S Ofosu-Amaah and D W Belcher},
  year = {1977},
  doi = {10.1136/bmj.1.6067.1009},
  url = {https://pubmed.ncbi.nlm.nih.gov/856396/},
  note = {Source identifier: 856396}
}