Cătinaş, Emil, and I Păvăloiu. “ On Approximating the Eigenvalues and Eigenvectors of Linear Continuous Operators”.
Rev. Anal. Numér. Théor. Approx. 26, no. 1 (August 1, 1997): 19–27. Accessed April 14, 2025.
https://ictp.acad.ro/jnaat/journal/article/view/1997-vol26-nos1-2-art3.