  We discuss the imaging properties of uniaxial epsilon-near-zero metamaterial
slabs with possibly tilted optical axis, analyzing their sub-wavelength
focusing properties as a function of the design parameters. We derive in closed
analytical form the associated two-dimensional Green's function in terms of
special cylindrical functions. For the near-field parameter ranges of interest,
we are also able to derive a small-argument approximation in terms of simpler
analytical functions. Our results, validated and calibrated against a full-wave
reference solution, expand the analytical tools available for
computationally-efficient and physically-incisive modeling and design of
metamaterial-based sub-wavelength imaging systems.
