On the identification of Fronimian with an addressee of Braulio's letters see Fear 1997, Lynch 1938, Valcárel Martinez 1990-1991. Some scholars thought that he was Braulio's brother (Lynch 1938; contra Fear 1997). In the correspondence he is referred to as "presbyter and abbot"; the latter title seems to indicate some monastic status and it was believed that he may have been an abbot of the San Millan de la Cogolla monastery, in the place where the oratory and the tomb of St Aemilian was. Here he is addressed only as a presbyter, thus the Life must have been written before Fronimian's elevation to monastic leadership. A.T. Fear, however, dismisses the possibility that Fronimian was an abbot in San Millan, because there is no contemporary evidence of the monastic activity at this place (the existence of the monastery is certain only from the 10th century (Ubieto Arteta 1973); for the Visigothic era only a church is mentioned; Fear 1997: 15, n. 1). It has been already demonstrated for the 6th century (Pietri 1982), the title of abba is not sufficient to assume the monastic status of a person, and there were also priests in charge of basilicas with this title. But we cannot assume that Fronimian was an abba basilicae in San Millan, because Braulio in his letter 13 to Fronimian ([101], see also letter 14 [296]) mentions "the brothers" who are under abbot Fronimian's supervision. If there was no monastery on the tomb of St Aemilian, Fronimian must have been a monastic superior elsewhere. But maybe the presbyter and abbot Citonatus, one of Braulio's sources about St Aemilian, was an abbot of the church in San Millan.
Citonatus, Gerontius, Sofronius and Potamia are not known from the other sources.