"With the connivance of Dr Heinz Fischer, a Swiss concert promoter, a German string quartet was invited to play in Zurich, bringing Paul's precious instruments from Vienna -- two violins, one by Stradivari, one by Guadagnini, a viola by Amati and a Rugieri cello. Nobody would notice, as they crossed the border at Haslach, that the instruments in their cases were not theirs. Nor would they spot when the musicians returned to the Reich with cheaper models under their arms than those with which they had left. Dr Fischer's and the musicians' payment for this risky undertaking is not known, nor is the fate of the two violins (perhaps the instruments were themselves the smugglers' reward),but in October 1938 Paul took the viola and cello to the Swiss violin maker Stübiger, who valued them at 18,000 Swiss francs each. A quick sale brought him [Paul] temporary financial relief."
The House of Wittgenstein: A Family At War, Alexander Waugh, The House of Wittgenstein: A Family At War, London