@misc{indiciae700290ced426,
  title = {On an extension problem for density matrices},
  author = {Carlen, Eric A. and Lebowitz, Joel L. and Lieb, Elliott H.},
  year = {2013},
  doi = {10.1063/1.4808218},
  url = {https://www.osti.gov/biblio/22163079},
  note = {Source identifier: 22163079}
}