  Due to the nonlinearity of QED, a static charge becomes a magnetic dipole if
placed in a magnetic field. Already without external field, the cubic Maxwell
equation for the field of a point charge has a soliton solution with a finite
field energy. Equations are given for self-coupling dipole moments. Any
theoretically found value for a multipole moment of a baryon or a meson should
be subjected to nonlinear renormalization.
