  The angular dependence of the thermal transport in insulating or conducting
ferromagnets is derived on the basis of the Onsager reciprocity relations
applied to a magnetic system. It is shown that the angular dependence of the
temperature gradient takes the same form as that of the anisotropic
magnetoresistance, including anomalous and planar Hall contributions. The
measured thermocouple generated between the extremities of the non-magnetic
electrode in thermal contact to the ferromagnet follows this same angular
dependence. The sign and amplitude of the magneto-voltaic signal is controlled
by the difference of the Seebeck coefficients of the thermocouple.
