  Hirota's discrete Korteweg-de Vries equation (dKdV) is an integrable partial
difference equation on 2-dimensional integer lattice, which approaches the
Korteweg-de Vries equation in a continuum limit. We find new transformations to
other equations, including a second-degree second-order partial difference
equation, which provide an unusual embedding into a three-dimensional lattice.
The consistency of the resulting system extends a property that has been widely
used to study partial difference equations on multidimensional lattices.
