The ascriptions "Leon" in E-V 10 (10r) and "Jº de Leon" in E-V 04 (36v), respectively, probably refer to Jerónimo León, chapelmaster at Valladolid cathedral between 1627 and 1629, but there is no list of works for this composer in the Diccionario (1999-2002). Juan de León (II), a contemporary chapelmaster at Segovia cathedral has sacred and secular production, but these two works ascribed to "León" in Valladolid have not been included in his list of works.
The only known work by Cristóbal Tello mentioned by González Marín is a "Kalenda Nativitatis D.N.J.C." (1587), 5 vv, at E-Zac, published by P. Calahorra, Obras de los maestros de las capillas de música de zaragoza en los siglos XV, XVI y XVII (Zaragoza: Instituto Fernando el Católico, 1984), pp. 67-71. The work attributed to Tellez in E-MO 2991 is hitherto unknown; the presence in that manuscript of works by Robledo and, especially Tellez, a kleinmeister active in Zaragoza, suggests that the manuscript comes from Zaragoza.