This must be distinct from the Fortún Sánchez who died in 1054 at the Battle of Atapuerca. The Historia Roderici says that the other two Castilian leaders were Diego Pérez and Lope Sánchez. de los Rios, José Amador (1863). "Capitulo 3: Primeros Monumentos Escritos de la Poesía Castellana (Chapter 3:First Written Monuments of Castilian Poetry)". Historia Crítica de la Literatura Española, Tomo III, (II Parte, Subciclo I) (The History and Criticism of Spanish Literature, Volume III, (Second Part, subpart I)) (in Spanish). Madrid, Spain: J. Rodriguez. p. 104.
