Salvatore and Gaetano wrote 2 books about Direct Restorations.
The first is Posterior Direct Restorations (available for now in Italian and German)
The second is Anterior Direct Restorations (available for now in Italian)
Posterior:
400 pages, 1800 pictures. Lots of clinical cases and tips and tricks.
Italian Publisher’s page of the book: Link
German Publisher’s page of the book: Link
Anterior:
462 pages, 2450 pictures. Lots of clinical cases and tips and tricks.
Publisher’s page of the book: Link
Here are some screenshots: