Karl Weierstrass - Karl Weierstrass – Über die analytische Darstellbarkeit sogenannter willkürlicher Functionen einer - 1885

First printing of the two communications by Karl Weierstrass on the analytic representability of arbitrary functions of a real variable. The work appeared in 1885 in the Proceedings of the Royal Prussian Academy of Sciences in Berlin. It contains the contribution later known as the Weierstrass Approximation Theorem. Both communications are bound together in a modern binding with marbled paper. The title pages bear library stamps and signatures. . The condition is evident from the photos.