@article{econhot_econhot-reading-41,
  title = {Determining the Number of Factors in Approximate Factor Models},
  author = {Jushan Bai and Serena Ng},
  journal = {Econometrica},
  year = {2002},
  volume = {70},
  number = {1},
  pages = {191-221},
  doi = {10.1111/1468-0262.00273},
  url = {https://doi.org/10.1111/1468-0262.00273}
}