A number of the covers in the above link were redrawn over the years - there's a selection of them
on this site.
Le Trésor du Brigand and
La Grande Pagaille are especially Tintinesque - or rather, Jo Zette & Jocko. The covers look more detailed than the interiors of the books, from the extracts on the Bédétheque site.
De Moor was incredibly skilled in adapting and changing his style, from his work with Hergé or completing EP Jacobs' last Blake and Mortimer volume, or even within the same series - Barelli undergoes stylistic changes between books as well as evolving naturally.
In addition to the site Jock mentioned above - which is an absolute treasure trove of rare artwork plus exemplary commentary - the book
Bob de Moor - 40 ans de bande dessinée - 35 ans aux côtés d'Hergé is worth seeking out. It contains interviews with Bob and his collaborators, artwork drawn from all his series, and a lengthy section on his work with Hergé, featuring amongst other things publicity material, sketches for
The Black Island and
The Red Sea Sharks, and his work on the animated films for Belvision.