Application of allogeneic adult mesenchymal stem cells in the treatment of venous ulcers: A phase I/II randomized controlled trial protocol - Víctor J. Costela-Ruiz; Encarnación González-Vigil; Olga Espinosa-Ibáñez; Rosario Mata Alcázar – Caballero; Lucía Melguizo-Rodríguez; Olga Fernández-López; Salvador Arias-Santiago (PLoS ONE, 2025)