@article{acanonicalrepresentationofblockmatrices,
  title = {A Canonical Representation of Block Matrices with Applications to Covariance and Correlation Matrices},
  author = {Ilya Archakov and Peter Reinhard Hansen},
  year = {2020},
  eprint = {2012.02698},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2012.02698v2},
}