exposition internationale du bureau à bâle by Theo Ballmer 1928

Theo Ballmer came from Lausanne where he worked in a printing firm he travelled to Zurich and studied under Ernst Keller at the Kunstgewerbeschule. In the 1920’s he studied at the Dessau Bauhaus under Paul Klee, Walter Gropius  and Hans Meyer. He later became an instructor at the Basel Allgemeine Gewerbeschule and taught there for some 30 years.

ref: Permanent collection of MOMA New York

The 20th Century Design of the Avant-Garde page 150