- Physics--History--20th century (2)
- Bohr, Niels, 1885-1962 (1)
- Einstein, Albert, 1879-1955--Political and social views (1)
- Gandhi, Mahatma, 1869-1948--Political and social views (1)
- Music and science--History--18th century (1)
- Music and science--History--19th century (1)
- Music and science--History--20th century (1)
- Music--Acoustics and physics--History--18th century (1)
- Music--Acoustics and physics--History--19th century (1)
- Music--Acoustics and physics--History--20th century (1)
- Nonviolence (1)
- Passive resistance (1)
- Physicists--Denmark--Biography (1)