[251] Quasiconformal maps in metric spaces with controlled geometry

[252] The combinatorial topology of analytic functions of the boundary of a disk

[253] Boundary behavior of a conformal mapping

[254] Zur Theorie der Quadratischen Reste

[255] On the representation of numbers in the form$ax$^{2}+$by$^{2}+$cz$^{2}+$dt$^{2}