Letter from W. Pauli to Teubner Verlagsgesellschaft. Related to the republication of "The theory of relativity".

Letter from Teubner Verlagsgesellschaft (Heisig) to W. Pauli. Related to the republication of "The theory of relativity".

Copy of a letter from G. Källén to W. Thirring. Källén comments Thirring's new calculation. Key words: cut-off size, Lee model, Pomeranchuk.

Reflections and calculations on the fundamental field as a 4x4 matrix $\Psi$ and on a Lagrangian invariance against transformation

Pauli mentions in this letter Einstein's rejection of Bohm and de Broglie, and Bohr's short visit to Zürich. He also writes on Plato's concepts of space and on the theory of representation, in particular the inhomogeneous group.

Pauli suggests that Fierz publish his investigations on the Lorentz group. He writes on certain eigenfunctions of the symmetrical top and their regular representation.