  In the framework of Clifford analysis, a chain of harmonic and monogenic
potentials in the upper half of Euclidean space $\mR^{m+1}$ was recently
constructed, including a higher dimensional analogue of the logarithmic
function in the complex plane. In this construction the distributional limits
of these potentials at the boundary $\mR^{m}$ are crucial. The remarkable
relationship between these distributional boundary values and four basic
pseudodifferential operators linked with the Dirac and Laplace operators is
studied.
