@misc{indiciae2512519499fd,
  title = {On the input-output stability of time-varying nonlinear feedback systems. I - Conditions derived using concepts of loop gain, conicity, and positivity.},
  author = {Zames, G.},
  year = {1966},
  url = {https://ntrs.nasa.gov/citations/19660057449},
  note = {Source identifier: 19660057449}
}