Here is the link to the book:
Alexandre Dumas - "Celebrated Crimes of the Borgias"
And yes, I agree. As I said, I mainly skimmed through it... some things were just a bit too lengthy in terms of the Medici did this, the Sforzas did that, the Orsinis opposed something else.
I found the beginning interesting, describing that Roderigo was perfectly happy in Spain with no ambitions until his uncle Pope Calixtus III. made him a cardinal and order him to Rome. Again, I wish there would have been some citations. I mean it's not like he doesn't cite any contemporary sources at all but... sometimes he puts a lot of judgement in his text and it's not quite clear where it's coming from.