The S...-criterion for Hankel forms on the Fock space, 0 < p < 1. Robert Wallstén — 1989 Mathematica Scandinavica
Density theorems for sampling and interpolation in the Bargmann-Fock space II. Kristian Seip; Robert Wallstén — 1992 Journal für die reine und angewandte Mathematik
A new look on Hankel forms over Fock space Svante Janson; Jaak Peetre; Robert Wallstén — 1989 Studia Mathematica