@misc{indiciae906a1d9c075a,
  title = {The Evolution of Nondestructive Evaluation Methods for the Space Shuttle External Tank Thermal Protection System},
  author = {Walker, James L. and Richter, Joel D.},
  year = {2006},
  url = {https://ntrs.nasa.gov/citations/20060014008},
  note = {Source identifier: 20060014008}
}