The integrability of N=16 supergravity

For the maximally extended N=16 supergravity theory in two dimensions, we explicitly construct a linear system whose integrability conditions are equivalent to the full nonlinear field equations of this theory. All the (on-shell) information contained in it can thus be encoded into a single E8 matrix and its dependence on a spectral parameter; the invariance of the equations of motion under E9 is manifest. Possible consequences and further developments are briefly discussed. (orig.)