@misc{indiciae945b613c4e43,
  title = {Active filters: some simple design methods for biomedical workers.},
  author = {C J Derrett and P J Tavner},
  year = {1975},
  doi = {10.1007/bf02478093},
  url = {https://pubmed.ncbi.nlm.nih.gov/1195881/},
  note = {Source identifier: 1195881}
}