Passage: Despite being named field marshal because of his military performance in the wars of the 1860s, Frederick did not receive the command of any troops after the Franco-Prussian war. In fact, the emperor did not trust his own son and tried to keep him away from state affairs because of his "too English" ideas. The crown prince was appointed "Curator of the Royal Museums", a task that raised some enthusiasm in his wife. Following the advice of her father, Victoria had continued her intellectual formation after arriving in Germany: she read Goethe, Lessing, Heine and Stuart Mill and frequented intellectual circles with her husband. The writer Gustav Freytag was a close friend of the couple and Gustav zu Putlitz was appointed Frederick's Chamberlain for some time. Despite the indignation of her mother, Vicky was also interested in the Theory of Evolution of Darwin and the ideas of British geologist Lyell. The German astronomer Wilhelm Julius Foerster reported that she visited the Berlin Observatory frequently and took keen interest in his astronomical work, and in the growth of the German Society for Ethical Culture. Eager to understand the principles of socialism, she read the work of Karl Marx and encouraged her husband to frequent the salon of Countess Marie von Schleinitz, a place known for being a meeting point of Bismarck's opponents.Unlike many of their contemporaries, Vicky and Frederick rejected antisemitism. In a letter to her mother, the crown princess harshly criticised the essay Das Judenthum in der Musik (Judaism in Music) by Richard Wagner, whom she considered ridiculous and unfair. As for Frederick, he did not hesitate to make public appearances in synagogues when manifestations began of hatred against the Jews in Germany, especially in the early 1880s. In 1880-1881, there was a campaign waged by the Völkisch movement to disemancipate German Jews, led by the Lutheran Pastor Adolf Stoecker and the historian Heinrich von Treitschke, leading to a quarter of million Germans signing a petition asking the...

Question: which physicians did the princely couple receive?
Hermann von Helmholtz and Rudolf Virchow