I think there’s some links or some such on my FR home page.
You can search Amazon.com for some Portugese researchers’ books on the topic.
They were very thoroughly and methodically researched . . . primary source materials from the time—the local Church even opened it’s secret files on it all for them. And, they interviewed survivors still alive at the time of their writing.
The nuts and bolts of it is not really a topic that I’m allowed to discuss any more on FR.
It will take some time yet for the truth to be faced.
There is solid evidence for miracles at Fatima, so apparition could not have been fake. One would have to show some heresy or falsehood being put forth by the apparition in order to prove it daemonic.