1. N. Bohr, ?Introductory survey?, in Atomic Theory and the Description of Nature (Cambridge University Press, Cambridge, [1929] 1934), pp. 1?24. Reprinted in Niels Bohr Collected Works, Vol. 6: Foundations of Quantum Physics I (1926?1932), J. Kalckar, ed. (North-Holland, Amsterdam, 1985), pp. 279?302.
2. Wirkungsquantum und Naturbeschreibung
3. N. Bohr, ?Quantum physics and philosophy: causality and complementarity?, in Philosophy in the Mid-Century: A Survey, R. Klibansky, ed. (La Nuova Italia Editrice, Firenze, 1958), pp. 308?314. Reprinted in Niels Bohr Collected Works, Vol. 7: Foundations of Quantum Physics II (1933?1958), J. Kalckar, ed. (North-Holland, Amsterdam, 1996), pp. 388?394.
4. Atomic Theory and Mechanics1