early 20th century Austrian postcard, based on the Mozart family portrait by Johann Nepomuk della Croce in Salzburg, which was commissioned by Leopold Mozart (1719-87); Maria Anna (Nannerl) (1751-1829) and Wolfgang Amadeus (1756-91) depicted playing four hands on a fortepiano; their father is shown with a violin and a quill pen and inkpot to show he was both a musician and a composer; behind the family is a portrait of Anna Maria Mozart (nee Pertl) (d.1777); statue of Apollo with lyre symbolizes the Mozart family dedication to the musical arts;