PPT Slide
A: "Zur Electrodynamik bewegter Körper” Annalen der Physik vol. XVII, June 1905
B: "Ist die Trägheit eines Körpers von seinem Energiegehalt abhängig?”
vol. XVIII, September 1905
Einstein wrote in 1905 a letter to his friend C. Habicht about B:
”A consequence of my work on electrodynamic just appeared to me: the principle of relativity, together with the fundamental equations of Maxwell implies that the mass is a direct measure of its content of energy and that light transports mass. A sensible reduction of mass should happen in the element radium...”
The only footnote or citation in Einstein’s article is an acknowledgment to his friend Besso for his “inspiration”