The autograph score of  Lalo’s much played concerto is lost; the only remaining sources are the  first edition score and parts as well as the autograph piano reduction by Lalo . Hugh Macdonald, the highly acclaimed editor of French music, has discovered that  Lalo’s  piano reduction was  used as a working score by  Lalo  himself. He continued  to make alterations to the work in the  reduction even after the work was officially published. These changes provide  for many  corrections in the solo part as we know it, but also call for some orchestral  passages to  be re-orchestrated to match up with  Lalo’s  final  alterations.<br>