https://books.google.fr/books?id=RLlo1bMNrrEC&printsec=frontcover&dq=Jean-Louis+Vieillard-Baron&hl=fr&sa=X&ei=c7ilVILNB--v7AbGtIDwDg&ved=0CCAQ6AEwAA#v=onepage&q=Jean-Louis%20Vieillard-Baron&f=false
https://books.google.fr/books?id=63MKzp08G7IC&printsec=frontcover&dq=Jean-Louis+Vieillard-Baron&hl=fr&sa=X&ei=c7ilVILNB--v7AbGtIDwDg&ved=0CCYQ6AEwAQ#v=onepage&q=Jean-Louis%20Vieillard-Baron&f=false
https://books.google.fr/books?id=63MKzp08G7IC&printsec=frontcover&dq=Jean-Louis+Vieillard-Baron&hl=fr&sa=X&ei=c7ilVILNB--v7AbGtIDwDg&ved=0CCYQ6AEwAQ#v=onepage&q=Jean-Louis%20Vieillard-Baron&f=false