@misc{indiciae5316ebc436d0,
  title = {Integrated Safety Analysis Tiers},
  author = {Shackelford, Carla and McNairy, Lisa and Wetherholt, Jon},
  year = {2009},
  url = {https://ntrs.nasa.gov/citations/20090034845},
  note = {Source identifier: 20090034845}
}