  The author presents a new proof of injectivity of the composition of the
inverse of the rational Chern Character in homology applied to the classifying
space BG of a (countable) discrete group G, restricted to dimensions less or
equal than two, with the rationalized Assembly map of Kasparov into the
(operator) K-Theory of the full group C^*-algebra C^*(G) (tensored with the
rational numbers).
