@article{DA,
      url = {http://digitalcollections.ohsu.edu/record/6823},
      title = {Artificial heart valves},
      abstract = {Digital scan of a 35mm slide. Image of two artificial  aortic heart valves placed side-bi-side on an orange-red  background. They have been set to show bottom and top views  of the valve. A white plastic ball is enclosed in a metal  cage with white mesh cloth-covered ring. A typed label  reads: AORTIC PROSTHESIS.},
      number = {DA},
      doi = {https://doi.org/10.6083/M4JM2893},
      recid = {6823},
}