This article states that the painting ‘Death of Marat’ in his bath is by Jacques-Louis David. It is not.
The picture you have provided is actually a copy of David’s original painting. It is by [Giuseppe Serangeli]. In addition to being a copy, it is inferior in every way.
The original by Jacques-Louis David is here: 
I do not know anything about Wikipedia editing, so I hope this post is ok.
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