That book is embarrasingly bad. I was impressed something that poor academically speaking came out of an university.
It's so bad that, most of the info they use is just gossip rag, they didn't even take the job of validating it or checking their sources. Such a basic thing and they weren't capable of it. For one, you can take the mention they do on the alleged "mass grave" found in the south of the country, "the biggest one in Latin America", which turned out to be nothing more than a cemetery. And there are many other examples.
sorry for bad English