Planck, Max, 1858-1947.
Original papers in quantum physics. Annotated by Hans Kangro. Translated by D. ter Haar and Stephen G. Brush.
Spectral energy distribution.
1972.
Planck, Max, 1858-1947. Zur Theorie des Gesetzes der Energieverteilung im Normalspectrum. English & German. 1973.
Planck's original papers in quantum physics.