• On additive generalization of Voronoi's theory to algebraic number fieldsLeibak, AlarProceedings of the Estonian Academy of Sciences. Physics. Mathematics2005 / 4, p. 195-211
• On definition of difference field, associated to nonlinear control system: several optionsKaldmäe, Arvo; Kotta, Ülle; Tõnso, MarisProceedings of the Estonian Academy of Sciences2026 / p. 97-105 https://doi.org/10.3176/proc.2026.2.01