Jean Jacques Rousseau

Cloned from a commemorative calender found in "Expérience", Place Antonin Poncet, Lyon, France. The calender titled Une Année Avec Jean Jacques Rousseau (A year with Jean Jacques Rousseau) was created on the occasion of his 400th anniversary and contains works of several famous artists. (Source)

I couldn't identify the master artist who created the original of this image. May be one of the reader can help. Thanks in advance.