The Sumerian language was spoken in Southern Mesopotamia starting around the fourth millennium BC. Though it was replaced with the Akkadian language around 2000 BC.
Jiménez Zamudio, Rafael. (1998) Gramática de la Lengua Sumeria: Gramática con ejercicios transliterados y en cuneiforme. Signario y Glosario. Torrecilla, Mercedes. (2004) ...