The files

- `include/Spectra/LinAlg/TridiagEigen.h`
- `include/Spectra/LinAlg/UpperHessenbergEigen.h`
- `include/Spectra/LinAlg/UpperHessenbergSchur.h`

were adapted from

- `Eigen/src/Eigenvaleus/SelfAdjointEigenSolver.h`
- `Eigen/src/Eigenvaleus/EigenSolver.h`
- `Eigen/src/Eigenvaleus/RealSchur.h`

in the [Eigen](http://eigen.tuxfamily.org/) library.

The authors for these three files were Gael Guennebaud <gael.guennebaud@inria.fr>
and Jitse Niesen <jitse@maths.leeds.ac.uk>.

The file `include/contrib/LOBPCGSolver.h` was originally contributed by Anna Araslanova.

The Jacobi-Davidson solvers were written by Felipe Zapata, Nicolas Renaud, Victor Azizi, Pablo Lopez-Tarifa
and Jens Wehner from the Netherlands eScience Center <J.Wehner@esciencecenter.nl>.

The [Catch](https://github.com/philsquared/Catch) library included for unit testing
was written by Phil Nash <github@philnash.me>.

Other part of Spectra was written by Yixuan Qiu <yixuan.qiu@cos.name>.
