  We prove quite general statements about functional equations in any number of
variables for the dilogarithms defined by Bloch-Wigner, Rogers, and Coleman,
showing that they follow from certain 5-term and 2-term relations in a precise
way. Unlike many other references, we use arbitrary coefficients, do not ignore
any torsion, and get sharp results. For the Bloch-Wigner dilogarithm, we also
consider complex conjugation, and for Coleman's p-adic dilogarithm we show
independence of the branch.
