French Defence book recommendation


"The Even More Flexible French" by Viktor Moskalenko
There is the more recent "The Fully-Fledged French" by the same author.
There are not a lot of "complete" books on the French of late. Mostly repertoire books. So the first thing you need to ask yourself is how you plan to answer 3.Nc3. 3...Bb4, 3...Nf6, or 3...dxe4. That will often decide which books to read.

Cheparinov's course in Modern Chess (videos+pgn) is very good IF the suggested lines are to your taste.
He advocates the Bd7+Nge7 line against the Advance Variation, the Qxd5/Qd6 line against the Tarrasch, 3...Nf6 with cxd4 and Qb6 against the Steinitz, and the Burn against the Bg5 line. All the lines are sound+computer checked.
It is not a complete course of the French, but rather a repertoire, it avoids very complicated variations, and it is aimed at mid to high level players (but this does not mean a weaker player cannot benefit from it).