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+\documentclass[10pt]{letter}
+\usepackage{UPS_letterhead,xcolor,mhchem,ragged2e,hyperref}
+\newcommand{\alert}[1]{\textcolor{red}{#1}}
+\definecolor{darkgreen}{HTML}{009900}
+
+
+\begin{document}
+
+\begin{letter}%
+{To the Editors of the Journal of Computational and Theoretical Chemistry,}
+
+\opening{Dear Editors,}
+
+\justifying
+Please find attached a revised version of the manuscript entitled 
+\begin{quote}
+  \textit{``A similarity renormalization group approach to Green’s function methods''}.
+\end{quote}
+      
+We thank the reviewers for their constructive comments.
+Our detailed responses to their comments can be found below.
+For convenience, changes are highlighted in red in the revised version of the manuscript. 
+
+We look forward to hearing from you.
+
+\closing{Sincerely, the authors.}
+
+\newpage
+
+%%% REVIEWER 1 %%%
+\noindent \textbf{\large Authors' answer to Reviewer \#1}
+
+\begin{itemize}
+
+\item 
+{The article of Marie and Loos describes a regularized GW approach inspired by the similarity renormalization group second-order perturbative analysis to the linear GW eigenvalue equations. The article is well-organized and the presentation is clear. I think this article can be accepted as is. Nonetheless, I do have a few minor suggestions.}
+\\
+\alert{We thank the reviewer for supporting publication of the present manuscript.
+}
+
+\item 
+{In Eq. (45), the authors mention a reverse approach where, if I understand correctly, the omega-dependent self-energy is directly modified using the SRG regularizer. How does this approach perform on GW50 and compare to qsGW and SRG-qsGW?}
+\\
+\alert{}
+
+\item 
+{I am a bit surprised that the SRG-qsGW converges all molecules for s = 1000 but not for s = 5000. The energy cutoff window is very narrow here: 0.032 - 0.014 Ha. Moreover, from Figs. 3, 4, and 6, the IPs are roughly converged in the order of s = 50 to a few 100. I think an analysis of the denominators $\Delta^{\nu}_{pr}$ for the typical molecules would be very informative. In particular, what are the several smallest denominators at the beginning and how do they change along the self-consistency procedure?}
+\\
+\alert{}
+
+\item 
+{In Eq. (18), I think $H^{\text{od}}$ is generally not a square matrix and it is better to say  $H^{\text{od}}(s)^\dagger H^{\text{od}}(s)$ instead of $H^{\text{od}}(s)^2$.}
+\\
+\alert{}
+
+\item 
+{I think the y axis (counts in each bin) should be presented in Figs. 5 and 7. Or at least the  limit of y axis should be fixed for all subplots in Fig. 5 or Fig. 7.}
+\\
+\alert{}
+
+\end{itemize}
+
+%%% REVIEWER 2 %%%
+\noindent \textbf{\large Authors' answer to Reviewer \#2}
+
+\begin{itemize}
+
+\item 
+{This is an excellent manuscript, which I very much enjoyed reading. In particular, it includes a comprehensive overview of the literature in the field, which I find very valuable (ref. 119 should be updated). The final result is an expression with a slighly different regularization as before, but it works well, is well founded, and is easy to implement. I don't see arguments against it.}
+\\
+\alert{We thank the reviewer for supporting publication of the present manuscript.
+}
+
+\item 
+{There are two issues that my be improved:
+1) The authors used the "dagger" symbol in eq. (21) and further, although they use real-valued spin-orbitals. In that case, also the matrices W are real. It seems more  consistent to either allow for complex-valued  spin-orbitals (e.g. in eq. (8)) or only use the matrix transpose.}
+\\
+\alert{}
+
+\item 
+{2) I find it somewhat disturbing to see positive and negative electron affinities. The authors may wish to comment briefly on the meaning of the sign.}
+\\
+\alert{}
+
+\end{itemize}
+
+%%%  %%%
+\noindent \textbf{\large Additional minor changes}
+
+\end{letter}
+\end{document}