  In [1], we proved the asymptotic achievability of the Cram\'{e}r-Rao bound in
the compressive sensing setting in the linear sparsity regime. In the proof, we
used an erroneous closed-form expression of $\alpha \sigma^2$ for the
genie-aided Cram\'{e}r-Rao bound $\sigma^2 \textrm{Tr}
(\mathbf{A}^*_\mathcal{I} \mathbf{A}_\mathcal{I})^{-1}$ from Lemma 3.5, which
appears in Eqs. (20) and (29). The proof, however, holds if one avoids
replacing $\sigma^2 \textrm{Tr} (\mathbf{A}^*_\mathcal{I}
\mathbf{A}_\mathcal{I})^{-1}$ by the expression of Lemma 3.5, and hence the
claim of the Main Theorem stands true.
  In Chapter 2 of the Ph. D. dissertation by Behtash Babadi [2], this error was
fixed and a more detailed proof in the non-asymptotic regime was presented. A
draft of Chapter 2 of [2] is included in this note, verbatim. We would like to
refer the interested reader to the full dissertation, which is electronically
archived in the ProQuest database [2], and a draft of which can be accessed
through the author's homepage under:
http://ece.umd.edu/~behtash/babadi_thesis_2011.pdf.
