Collectio Florentina
The Ballerini described a collection (their no. 13) of genuine and forged decretals found in a twelfth-century Florentine manuscript. It contains 23 letters of Leo and parts of another one. The Ballerini note the influence of Pseudoisidore, but also the different arrangement and textual differences. They valued the collection highly mainly because ep. 12 was found here and only here in its complete form ("integra").
According to Hoskin, who renamed the collection Florentina, it contains 24 letters of Leo; p. 369 he notes that the Florentina "is the only source for the allegedly complete form of Ep. 12 as published by the Ballerini", but found that this "complete form" is nothing but a combination of two shorter versions of ep. 12 (JK 410).
The Florence manuscript is not to be confused with Firenze, Biblioteca Nazionale Centrale, Conv. Soppr. J.IV.20 (San Marco 182), a late-medieval copy of astronomical works. Rather, as Hoskin established, the manuscript the Ballerini called "San Marco 182" most likely is to be identified with Firenze, Biblioteca Nazionale Centrale, Conv. soppr. J.III.18, normally classified as Pseudoisidore A1.