@misc{indiciaed692d8ad83b6,
  title = {Nonlinear techniques for forecasting solar activity directly from its time series},
  author = {Ashrafi, S. and Roszman, L. and Cooley, J.},
  year = {1993},
  url = {https://ntrs.nasa.gov/citations/19930015527},
  note = {Source identifier: 19930015527}
}