Ahrens, B., & Lumsdaine, P. L. F. (2019). Displayed Categories. Logical Methods in Computer Science, 15(1). https://doi.org/10.23638/LMCS-15(1:20)2019 arXiv:1705.04296. 
@article{ahrens-lumsdaine:2019,
  author = {Ahrens, Benedikt and Lumsdaine, Peter LeFanu},
  url = {https://lmcs.episciences.org/5252},
  year = {2019},
  month = mar,
  doi = {10.23638/LMCS-15(1:20)2019},
  eprint = {1705.04296},
  eprinttype = {arXiv},
  issue = {1},
  journal = {Logical Methods in Computer Science},
  title = {Displayed Categories},
  volume = {15}
}