Camas Pereyra, Rausel , Camas-Gómez, Robertony , Ramírez-Valverde, Gustavo  Padilla-Cuevas, Juliana  Etchevers, Effect of gypsum and potassium on corn yield and on the exchangeable bases of an acid soil in La Frailesca, Chiapas 2023/17, DOI  – 10.32854/agrop.v15i12.2287  (PDF) Effect of gypsum and potassium on corn yield and on the exchangeable bases of an acid soil in La Frailesca, Chiapas (researchgate.net)