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\begin{document}
\let\raggedleft\raggedright
%\address{}
\signature{Min Yang\\
%\signature{Wei An\\
  %Professor, State Key Laboratory of Environmental Aquatic Chemistry\\
  State Key Laboratory of Environmental Aquatic Chemistry\\
  Research Center for Eco-Environmental Sciences\\
  Chinese Academy of Sciences\\
  P. O. Box 2871, Beijing, 100085 China\\
  Tel: 86-10-62923475;\\
  Fax: 86-10-62923541\\
  E-mail: \href{mailto:yangmin@rcees.ac.cn}{yangmin@rcees.ac.cn}\\
  %E-mail: anwei@rcees.ac.cn\\
}
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\begin{letter}{}
  \opening{The Editor of \textit{Water Research}\\[2ex]\\Dear Sir,\\[-3ex]}
  \noindent

  The accompanying full-length article entitled: ``\textit{\textbf{Establishment of quantitative PCR methods for
    quantification of geosmin-producing potential and \textit{Anabaena} sp.~in freshwater systems}}" is the revised
    version of the manuscript (\textbf{WR21535}, revision NO.: \textbf{WR21535R1}) for publication in
    \textbf{\textit{Water Research}}.

    Thank you for your kind consideration of our paper. According to the comments and suggestions of the reviewer, we
    have carefully revised this manuscript, a new paragraph was added to enhance the novelty by comparing with other
    studies; besides, some spelling errors were corrected. 

    The point to point responses to your and reviewers' comments are shown in a separate sheet labeled as
    ``\textbf{Revision Note}'', with the normal text indicates the original comments and the bold text indicates our
    responses. The blue fonts (such as \S\ref{new-resdiss} \nameref{new-resdiss}, and Figure \ref{apd-fig:arganova}) in
    the revised Manuscript or revised Supporting Information indicate the hyper link to corresponding positions. Please
    click it if you want to see the details in the Manuscript or Supporting Information (Please download the
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    \href[pdfnewwindow]{Supporting\veraa.pdf}{\textbf{Supporting\veraa.pdf}} with the links given in the last two pages of this file
    \textbf{WR21535R2.pdf}, and store them with this file in the same folder in your computer with the default filename
    (ManuscriptNew\veraa.pdf, Supporting\veraa.pdf)).  I believe that the quality and readability of this revised
    manuscript have been significantly improved.

    \closing{Yours sincerely,}

    \end{letter}
    \end{document}