@misc{1195836,
  author = {L Chen},
  title = {Recommendation for key derivation using pseudorandom functions (revised):},
  year = {2009},
  month = {2009-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NIST.SP.800-108},
  language = {en},
}