The most obvious choice would be Antoine Prunet's book, Ferrari Sports Cars and Prototypes. It's a usually bit expensive (+50€) but if you're patient good solid copies often surface at 'low' prices (15-25), which is how I got mine.
It covers the P series, and there's also a small chapter about the P4-derived 612 and the 512-derived 712. I don't have a scanner but I can take pics with my cellphone if you need.
The 2nd and 3rd choices I can't tell much because they're on my wish list
Those would be Pete Lyons Can-Am book, which is considered the best on the series; and more appropriately, Anthony Pritchard's Scarlet Passion, which covers Ferrari's Prototypes race history in the 60s-70s.
Edited by guiporsche, Jan 28 2018 - 09:23 AM.