1. G. Sarton:Introduction to the History of Science, 5 volumes (Carnegie Institution of Washington, D. C., 1927 to 1947).
2. H. A. Bethe:Rev. Mod. Phys.,8, 193 (1936);H. A. Bethe andR. F. Bacher:Rev. Mod. Phys.,9, 71 (1937).
3. A. Einstein:Verth. Dtsch. Phys. Ges.,19, 82 (1917).
4. A. Koyré:Galilée et la loi d'inertie (Hermann, Paris, 1939).
5. S. Drake:Galileo Studies (The University of Michigan Press, Ann Arbor, Mich., 1970), Chapt. 12.