401. That’s an error.

Your client does not have permission to the requested URL /books?id=yeMUAAAAQAAJ&pg=PA225&lpg=PA225&dq=la+vengeance+comme+sentiment&source=bl&ots=sIzm24dmNQ&sig=HFU6aIZjkfQHEKxRmI7G3EuiCKY&hl=fr&sa=X&ei=W8dxVPiSDMzcar_1gpgH&redir_esc=y. That’s all we know.