Kemmer gives more calculations on the wave equation and makes a comparison with de Broglie's results.

Salam replies to Pauli's remarks about C, P or T conservation. He writes about some possible forms of writing down the $\beta$-decay interaction.

Salam writes about Pauli's criticisms of his note. He writes about the revivial of the neutrino theory of light.

Critical remarks from Kemmer about Bhabha's calculations on the neutretto-meson theory and remarks on the Bremstrahlung of the meson.

Kemmer gives a development of a convenient formalism for the wave equation, different from the usual representation of Dirac's Hamiltonian.