What is the last name of the person whose initial musical education is unclear?  Answer the above question based on the context below:  George Frideric Handel was born on 23 February 1685 in the German city of Halle. It is unclear what initial musical education he received; his father, Georg Händel, was not a music lover, and did not at first appreciate or encourage his son's precocious talents. Nevertheless, by the age of ten Handel had become an accomplished organist; his playing in the royal chapel at Weissenfels, where his half-brother Karl was in the service of the Duke of Saxe-Weissenfels, impressed the duke, who persuaded Händel senior that the boy should have a proper musical education. As a result, Handel began formal study under Friedrich Zachow, the organist of the Lutheran church at Halle.Handel's biographer Jonathan Keates writes that: "From [Zachow] Handel learned not only a great deal about the line and shape of an aria, about strong, adventurous bass lines and solid choral writing, but also about those delicacies of instrumental colouring which he later perfected in his own style". Handel's musical development also benefited from an early and lasting friendship with Georg Philipp Telemann, whom he met in 1700. In February 1702 Handel enrolled at the University of Halle, perhaps intending to study law. In March he took up the post of organist at Halle's Calvinist cathedral (Domkirche), a prestigious appointment for one so young and indicative of his burgeoning musical reputation in the city.At some time, possibly in late 1702 or early 1703, Handel visited Berlin, where his father had held an honorary post as physician to the elector who, in 1701, had become the Prussian king Frederick I. In Berlin Handel first experienced Italian opera, and may have met the Italian composers Giovanni Bononcini and Attilio Ariosti, who were writing operas for Frederick's court. The king heard of Handel's abilities, and wanted him to train as a future court composer, but Handel's horizons had been broadened by his sojourn in Berlin and he was developing his own ideas for his future. He declined the king's offer, and returned to Halle to fulfil...
Handel