@misc{indiciaeb3da1cb2f04e,
  title = {A scalable matrix-free spectral element approach for unsteady PDE constrained optimization using PETSc/TAO},
  author = {Marin, Oana and Constantinescu, Emil and Smith, Barry},
  year = {2020},
  doi = {10.1016/j.jocs.2020.101207},
  url = {https://www.osti.gov/biblio/1776612},
  note = {Source identifier: 1776612}
}