@misc{zhou2023theory,

      title={Theory of functional principal component analysis for noisy and discretely observed data}, 

      author={Hang Zhou and Dongyi Wei and Fang Yao},

      volume = {53},

      year={2025},

      journal = {The Annals of Statistics},

      number = {5},

      pages = {2103 -- 2127},

      doi = {10.1214/25-AOS2531}, 

}