• We located the CeBIT electronics exhibition in the wrong German city (8 March, p 26). It takes place in Hannover.
• The “dark fluid” on which HongSheng Zhao and colleagues have based their modified Newtonian dynamics (MOND) theory is not, as we stated (8 March, p 10), a mixture of dark matter and dark energy. What Zhao envisages is something different from either that mimics the effects of both.
• It was Norway, not Sweden, that contributed $5 million to a nuclear fuel bank (8 March, p 7).
