Critical Graphs for the Positive Definite Completion Problem. - Wayne W. Barrett; Charles R. Johnson; Raphael Loewy (SIAM J. Matrix Anal. Appl., 1998)

A Note on the Symmetric Recursive Inverse Eigenvalue Problem. - Raphael Loewy; Volker Mehrmann (SIAM J. Matrix Anal. Appl., 2003)

Nonnegative Matrices That Are Similar to Positive Matrices. - Thomas J. Laffey; Raphael Loewy; Helena Smigoc (SIAM J. Matrix Anal. Appl., 2009)