It is for him to quote authorities for what he writes, and not to be set up as an authority.

He is not reliable, and he is a notorious defamer of the Papacy, sparing nothing that will serve his ends.

He dilates with gusto upon the accusation of incest.
Lastly, PANVINTO is in the same category as Guicciardini.

He was not born until some thirty years after these events, and his History of the Popes was not written until some sixty years after the murder of the Duke of Gandia.

This history bristles with inaccuracies; he never troubles to verify his facts, and as an authority he is entirely negligible.
In the valuable Diarium of Burchard there is unfortunately a lacuna at this juncture, from the day after the murder (of which he gives the full particulars to which we have gone for our narrative of that event) until the month of August following.