| 2005 |
On the nonnegativity of operator products |
Hassi Seppo;Sebesty'en Zoltan and de Snoo Henk |
| 2005 |
Q-functions of Hermitian contractions of Krein-Ovcharenko type |
Arlinskii Yury;Hassi Seppo;de Snoo Henk |
| 2004 |
Singular Sturm-Liouville problems whose coefficients depend rationally on the eigenvalue parameter. |
Hassi, Seppo; Möller, Manfred; de Snoo, Henk |
| 2004 |
Similarity of J-selfadjoint Sturm-Liouville operators with an operator potential to selfadjoint ones. |
Hassi;Seppo and Ilia Karabash |
| 2004 |
Boundary relations and their Weyl families |
Derkach;Vladimir;Seppo Hassi;Mark Malamud;and Henk de Snoo |
