An Analysis of Universality in Blackbody Radiation
  Through the formulation of his law of thermal emission, Kirchhoff conferred upon blackbody radiation the quality of universality [G.Kirchhoff, Annalen der Physik 109, 275 (1860)]. Consequently, modern physics holds that such radiation is independent of the nature and shape of the emitted object. Recently, Kirchhoff's experimental work and theoretical conclusions have been reconsidered [P.M.L. Robitaille, IEEE Transactions on Plasma Science 31(6), 1263 (2003). In this work, Einstein's derivation of the Planckian relation is reexamined. It is demonstrated that claims of universality in blackbody radiation are invalid. 
Pierre-Marie Robitaille