RT Journal Article T1 Semitoric systems of non-simple type A1 Palmer, Joseph A1 Pelayo González, Álvaro A1 Tang, Xiudi AB Within integrable systems, the class of so called “semitoric” integrable systems in dimension four has attracted a lot of attention in recent years, especially since fundamental examples from classical and quantum mechanics have been identified as semitoric by different groups of researchers. Several of these examples, however, show a particular trait not included in the original theory, that is, the presence of multiple (i.e. two or more) rank zero isolated singularities in the same energy-momentum level sets. Systems with this property are called non-simple. This paper extends the original theory of Pelayo and Vũ Ngọc to non-simple systems. PB Springer SN 1578-7303 SN 1579-1505 YR 2024 FD 2024 LK https://hdl.handle.net/20.500.14352/129214 UL https://hdl.handle.net/20.500.14352/129214 LA eng NO Palmer, J., Pelayo, Á. & Tang, X. Semitoric systems of non-simple type. Rev. Real Acad. Cienc. Exactas Fis. Nat. Ser. A-Mat. 2024 Sept 24; 118 (4): 161. DS Docta Complutense RD 30 dic 2025