  Two exact relations between mutlifractal exponents are shown to hold at the
critical point of the Anderson localization transition. The first relation
implies a symmetry of the multifractal spectrum linking the multifractal
exponents with indices $q<1/2$ to those with $q>1/2$. The second relation
connects the wave function multifractality to that of Wigner delay times in a
system with a lead attached.
