| 1906, 23 December. | Niels Bohr | Harald Bohr |
| 1906, 26 December. Voksenkollen. | Niels Bohr | Harald Bohr |
| 1909, 25 February. | Harald Bohr | Niels Bohr |
| 1909, 26 February. | Harald Bohr | Niels Bohr |
| [1909, 29 March]. | Harald Bohr Ellen Bohr | Niels Bohr |
| 1909, 6 March. | Harald Bohr | Niels Bohr |
| 1909, 12 March. | Niels Bohr | Harald Bohr |
| 1909, 13 March. | Harald Bohr | Niels Bohr |
| 1909, 15 March. | Harald Bohr | Niels Bohr |
| 1909, 17 March. | Niels Bohr | Harald Bohr |
| 1909, 20 March. | Harald Bohr | Niels Bohr |
| 1909, 22 March. | Ellen Bohr Harald Bohr | Niels Bohr |
| 1909, 24 March. | Harald Bohr | Niels Bohr |
| 1909, 25 March. | Harald Bohr | Niels Bohr |
| [1909, 25 March]. | Niels Bohr | Harald Bohr |
| 1909, 27 March. | Harald Bohr | Niels Bohr |
| [1909, 27 March]. | Niels Bohr | Harald Bohr |
| [1909, 11 April]. s’Gravenhage. | Harald Bohr | Niels Bohr |
| 1909, 20 April. | Niels Bohr | Harald Bohr |
| 1909, 24 April. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 26 April. | Niels Bohr | Harald Bohr |
| 1909, 28 April. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 4 May. | Niels Bohr | Harald Bohr |
| 1909, 6 May. Göttingen | Harald Bohr | Niels Bohr |
| 1909, 12 May. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 12 May. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 15 May. | Niels Bohr | Harald Bohr |
| 1909, 9 June. | Niels Bohr | Harald Bohr |
| [1909, 10 June]. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 18 June. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 1 July. | Niels Bohr | Harald Bohr |
| 1909, 4 July. København | Niels Bohr | Harald Bohr |
| 1909, 23 July. | Niels Bohr | Harald Bohr |
| [1909, 11 August]. Göttingen. | Harald Bohr | Niels Bohr |
| 1909, 12 August. | Niels Bohr | Harald Bohr |
| 1909, 18 August. | Niels Bohr | Harald Bohr |
| 1909, 8 September. Nærum. | Niels Bohr | Harald Bohr |
| 1909, 2 November. | Harald Bohr | Niels Bohr |
| 1909, 7 November. | Niels Bohr | Harald Bohr |
| [1909, 9 November]. | Niels Bohr | Harald Bohr |
| [1909, 20 December]. | Niels Bohr | Harald Bohr |
| 1909, 25 December. København | Christian Bohr Harald Bohr | Niels Bohr |
| [1909,] 26 December. | Harald Bohr | Niels Bohr |
| [1909,] 31 December. | Harald Bohr | Niels Bohr |
| [1910, 23 June]. | Harald Bohr | Niels Bohr |
| 1910, 25 June. | Niels Bohr | Harald Bohr |
| 1910, 26 June. København | Niels Bohr | Harald Bohr |
| 1910, 27 June. | Harald Bohr | Niels Bohr |
| 1910, 28 June. | Harald Bohr | Niels Bohr |
| 1910, 29 June. Göttingen. | Harald Bohr | Niels Bohr |
| 1910, 5 July. | Niels Bohr | Harald Bohr |
| 1910, 21 July. Göttingen | Harald Bohr | Niels Bohr |
| 1910, 28 July. | Niels Bohr | Harald Bohr |
| 1910, 30 July. Göttingen. | Harald Bohr | Niels Bohr |
| 1910, 21 August. København | Harald Bohr | Margrethe Nørlund Niels Bohr |
| 1910, 26 August. København | Harald Bohr | Niels Bohr Margrethe Nørlund |
| 1910, 24 November. Vissenbjerg. | Niels Bohr | Harald Bohr |
| 1910, 26 November. København | Harald Bohr | Niels Bohr |
| 1910, 29 December. Rom. | Harald Bohr | Niels Bohr Margrethe Nørlund |
| 1911, 2 January. | Niels Bohr | Harald Bohr |
| 1911, 22 April. | Niels Bohr | Harald Bohr |
| [1911, 4 July]. Göttingen. | Harald Bohr | Niels Bohr |
| 1911, 29 September. Cambridge. | Niels Bohr | Harald Bohr |
| 1911, 4 Oktober. København | Harald Bohr | Niels Bohr |
| 1911, 4 Oktober. Cambridge. | Niels Bohr | Harald Bohr |
| 1911, 23 October. Cambridge. | Niels Bohr | Harald Bohr |
| 1911, 11 December. Cambridge. | Niels Bohr | Harald Bohr |
| 1911, 14 December. Cambridge. | Niels Bohr | Harald Bohr |
| 1911, 19 December. Cambridge. | Niels Bohr | Harald Bohr |
| [1911,] 21 December. | Harald Bohr Ellen Bohr | Niels Bohr |
| [1912, 8 January]. London. | Harald Bohr | Ellen Bohr |
| [1912, 8 January]. | Harald Bohr | Ellen Bohr |
| 1912, 9 January. | Harald Bohr Niels Bohr | Ellen Bohr |
| 1912, 20 January. Cambridge. | Niels Bohr | Harald Bohr |
| 1912, 28 January. Cambridge. | Niels Bohr | Ellen Bohr Harald Bohr |
| 1912, 29 January. Cambridge. | Niels Bohr | Ellen Bohr Harald Bohr |
| 1912, 30 January. København | Harald Bohr | Niels Bohr |
| 1912, 5 February. Cambridge. | Niels Bohr | Ellen Bohr Harald Bohr |
| 1912, 9 February. Cambridge. | Niels Bohr | Harald Bohr |
| 1912, 19 February. Cambridge. | Niels Bohr | Ellen Bohr Harald Bohr |
| 1912, 19 February. Cambridge. | Niels Bohr | Ellen Bohr |
| 1912, 7 March. Cambridge. | Niels Bohr | Harald Bohr |
| 1912, 13 March. København | Harald Bohr | Niels Bohr |
| 1912, 7 April. København | Harald Bohr | Carl Wilhelm Oseen |
| 1912, 18 April. Manchester. | Niels Bohr | Harald Bohr |
| 1912, 19 May. Manchester. | Niels Bohr | Harald Bohr |
| 1912, 23 May. Hareskov Kuranstalt. | Harald Bohr | Niels Bohr |
| 1912, 27 May. Manchester. | Niels Bohr | Harald Bohr |
| 1912, 28 May. | Niels Bohr | Harald Bohr |
| 1912, 12 June. Manchester. | Niels Bohr | Harald Bohr |
| 1912, 19 June. Manchester. | Niels Bohr | Harald Bohr |
| 1912, 29 June. | Harald Bohr | Niels Bohr |
| 1912, 17 July. Manchester. | Niels Bohr | Harald Bohr |
| 1912, 22 July. Manchester. | Niels Bohr | Harald Bohr |
| [1912, 9 August]. Tisvilde. | Hanna Adler Harald Bohr | Niels Bohr Margrethe Bohr |
| 1912, 9 August. Tisvilde. | Harald Bohr | Niels Bohr Margrethe Bohr |
| [1912, 11 November]. | Harald Bohr | Niels Bohr Margrethe Bohr |
| 1912, 23 December. | Niels Bohr | Harald Bohr |
| [1913, 25 July]. | Harald Bohr | Niels Bohr |
| 1913, 30 July. Cambridge. | Niels Bohr | Harald Bohr |
| [1913, August]. | Harald Bohr | Ellen Bohr |
| 1913, 3 August. Cambridge. | Niels Bohr | Harald Bohr |
| 1913, 8 August. Göttingen. | Harald Bohr | Niels Bohr |
| 1913, 8 August. Esbjerg. | Niels Bohr | Harald Bohr |
| 1913, 10 August. Kolding. | Niels Bohr | Harald Bohr |
| [1913]. Göttingen. | Harald Bohr | Niels Bohr |
| 1913, 13 December. København | Niels Bohr | Harald Bohr |
| 1914, 17 March. København | Niels Bohr | Harald Bohr |
| 1914, 20 March. Garmisch-Partenkirchen. | Harald Bohr | Niels Bohr |
| 1914, 20 April. København | Niels Bohr | Harald Bohr |
| 1914, 1 November. Manchester. | Niels Bohr | Harald Bohr |
| 1915, 6 January. Fredensborg. | Harald Bohr | Niels Bohr |
| 1915, 24 February. | Harald Bohr | Niels Bohr |
| 1915, 2 March. Manchester. | Niels Bohr | Harald Bohr |
| [1915,] 9 March. Manchester. | Niels Bohr | Harald Bohr |
| 1915, 13 March. Manchester. | Niels Bohr | Harald Bohr |
| 1915, 18 March. København | Harald Bohr | Niels Bohr |
| 1915, 15 April. Manchester. | Niels Bohr | Harald Bohr |
| [1915, 17 April]. | Harald Bohr | Niels Bohr |
| 1915, 27 April. København | Harald Bohr | Niels Bohr |
| 1915, 5 May. Manchester. | Niels Bohr | Harald Bohr |
| 1915, 29 July. Chapel-en-le-Frith. | Niels Bohr | Harald Bohr |
| 1915, 10 October. Manchester. | Niels Bohr | Harald Bohr |
| 1916, 16 January. Fredensborg. | Harald Bohr | Niels Bohr |
| 1916, 8 March. Fredensborg. | Harald Bohr | Niels Bohr |
| 1916, 14 March. Manchester. | Niels Bohr | Harald Bohr |
| 1919, 16 April. London. | Niels Bohr | Harald Bohr |
| 1922, 31 March. Arundel. | Niels Bohr | Harald Bohr |
| 1925, 23 August. Als. | Harald Bohr | Niels Bohr |
| 1926, 5 January. Paris. | Harald Bohr | Niels Bohr |
| 1927, 17 July. Skagens Havn. | Niels Bohr | Harald Bohr |
| 1927, 26 September. Azzano. | Niels Bohr | Harald Bohr |
| 1927, 22 October. | Harald Bohr | Niels Bohr |
| 1927, 1 December. København | Niels Bohr | Harald Bohr |
| [1928,] 22 August. Fynshav. | Harald Bohr | Niels Bohr |
| 1929, 10 June. København | Niels Bohr | Harald Bohr |
| 1930, 5 January. Hundorp. | Niels Bohr | Harald Bohr |
| 1930, 20 September. Carmel, Californien. | Harald Bohr | Niels Bohr |
| 1930, 4 December. København | Niels Bohr | Harald Bohr |
| 1930, 29 December. Palo Alto. | Harald Bohr | Niels Bohr |
| 1931, 11 January. Dombås. | Niels Bohr | Harald Bohr |
| 1931, 14 January. Dombås. | Niels Bohr | Harald Bohr |
| 1931, 12 April. København. | Niels Bohr | Harald Bohr |
| [1931, 19 September]. | Harald Bohr | Margrethe Bohr |
| 1931, 12 November. Spa, Belgien. | Niels Bohr | Harald Bohr |
| 1933, 29 April. M.V. “Britannic”. | Niels Bohr | Harald Bohr |
| 1933, 12 May. København. | Harald Bohr | Niels Bohr |
| 1933, 15 May. Pasadena. | Niels Bohr | Harald Bohr |
| 1937, 1 April. Berkeley, Californien. | Niels Bohr | Harald Bohr |
| 1937, 5 May. Charlottenlund. | Harald Bohr | Niels Bohr |
| 1938, 1 March. Vinstra, Norge. | Niels Bohr | Harald Bohr |
| 1944, 3 April. Washington D.C. | Niels Bohr | Harald Bohr |
| 1945, 1 January. Washington D.C. | Niels Bohr | Harald Bohr |
| 1945, 15 May. København. | Harald Bohr | Niels Bohr |
| 1945, 6 July. Charlottenlund. | Harald Bohr | Niels Bohr |
| 1945, 10 July. | Harald Bohr | Niels Bohr |
| 1946, 13 October. København. | Harald Bohr | Niels Bohr |
| 1949, 17 August. Fynshav. | Harald Bohr | Niels Bohr |
| 1950, 7 April. København. | Harald Bohr | Niels Bohr |
| 1950, 14 April. København. | Harald Bohr | Niels Bohr |
| [1950, 15 April]. København. | Harald Bohr | Niels Bohr |
| 1950, 20 April. Princeton, New Jersey. | Niels Bohr | Harald Bohr |
| 1950, 24 April. København. | Harald Bohr | Niels Bohr |
