  The unique determination of a measurable conductivity from the
Dirichlet-to-Neumann map of the equation $\mathrm{div} (\sigma \nabla u) = 0$
is the subject of this note. A new strategy, based on Clifford algebras and a
higher dimensional analogue of the Beltrami equation, is here proposed. This
represents a possible first step for a proof of uniqueness for the Calder\'on
problem in three and higher dimensions in the $L^\infty$ case.
