TY - JOUR AU - Fernando Galván, José Francisco PY - 2021 DO - 10.1007/s12220-021-00721-1 UR - https://hdl.handle.net/20.500.14352/96132 T2 - Journal of Geometric Analysis LA - eng M2 - 12375 TI - Positive Semidefinite Analytic Functions on Real Analytic Surfaces TY - journal article VL - 31 ER -