Leopold Auer
"Henri Vieuxtemps preferred Kittel bows even to those of F.X. Tourte. Since then, Kittel's bows have been used by the greatest soloists, among them Henryk Wieniawski, Jascha Heifetz, Mischa Elman, Toscha Seidel, Leopold Auer, Isaac Stern, Paul Kochanski, Aaron Rosand, Erica Morini, Efrem Zimbalist, Leonid Kogan, Yehudi Menuhin, and Vadim Repin. Kittel bows are extremely rare.