Disabling backref in secondary multibib bibliography with natbib

I am finalising my PhD thesis that I have composed with LaTeX.

I have a section in which I list my own publications and the whole list of references at the very end of the document. This list is rather long and I decided to include back references to ease the reading. I used a combination of natbib, multibib and backref. Unfortunately, this enabled them on the secondary bibliography containing my own publications as well.

How am I supposed to disable back references for publications and enables them for the bibliography? I think I burnt my brain and I can not find a solution on my own! Anyway, please find attached a minimal working example.

Bonus question: I included my own works in publications.bib and I repeated them in biblio,bib (the main bibliography DB) adding a copy suffix to their keys, not to mess with them. Is there a more clever way than the one I pursued to cite them and list them in the Publications paragraph of the thesis, and list them in the main bibliography with all the back references but those in the Publications paragraph?

main.tex

\documentclass{scrreprt}

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

\usepackage[square,numbers,sort&compress]{natbib}
\usepackage[resetlabels]{multibib}
\newcites{publications}{\null}

\usepackage[pdftex]{hyperref}
\usepackage[hyperpageref]{backref}
\usepackage{bookmark}

\newcommand{\backrefnotcitedstring}{\relax} %(Not cited.)
\newcommand{\backrefcitedsinglestring}[1]{\\\textsmaller{(Cited on page~#1)}}
\newcommand{\backrefcitedmultistring}[1]{\\\textsmaller{(Cited on pages~#1)}}
\renewcommand{\backreftwosep}{ and~} % separate 2 pages
\renewcommand{\backreflastsep}{, and~} % separate last of longer list
\renewcommand*{\backref}[1]{}  % disable standard
\renewcommand*{\backrefalt}[4]{\ifcase #1 \backrefnotcitedstring \or \backrefcitedsinglestring{#2} \else \backrefcitedmultistring{#2} \fi}

\begin{document}
\chapter*{Publications}
Some ideas and figures have previously and partially appeared in \citep{me2012a,me2012b}.
\begingroup
\let\clearpage\relax
\vspace{-6ex}
\nocitepublications{*}
\bibliographystylepublications{abbrvnat}
\bibliographypublications{publications}
\endgroup

\chapter{Introduction}
In this thesis I take some of the concepts that I introduced in \citep{me2012acopy,me2012bcopy} and I quote others proposed in \citep{he2011,she2011,them2011}.

\appendix
\bibliographystyle{abbrvnat}
\bibliography{biblio}
\end{document}


publications.bib

@article {me2012a,
author = {Me, I},
title = {Title 1},
journal = {A Journal},
journaltitle = {A Journal},
year = {2012}
}

@article {me2012b,
author = {Me, I},
title = {Title 2},
journal = {A Journal},
journaltitle = {A Journal},
year = {2012}
}


biblio.bib

@article {me2012acopy,
author = {Me, I},
title = {Title 1},
journal = {A Journal},
journaltitle = {A Journal},
year = {2012}
}

@article {me2012bcopy,
author = {Me, I},
title = {Title 2},
journal = {A Journal},
journaltitle = {A Journal},
year = {2012}
}

@article {he2011,
author = {He, Author},
title = {Title He},
journal = {A Journal},
journaltitle = {A Journal},
year = {2011}
}

@article {she2011,
author = {She, Author},
title = {Title She},
journal = {A Journal},
journaltitle = {A Journal},
year = {2011}
}

@article {them2011,
author = {Them, Authors},
title = {Title Them},
journal = {A Journal},
journaltitle = {A Journal},
year = {2011}
}

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Hi, thanks for replying! Weird, it solves the problem in the minimal example, but not the whole thesis... In fact it is the first thing I tried myself! I'll investigate the other things that I stripped from the project to get the MWE. Thanks anyway! –  Stefano Bragaglia Apr 11 '13 at 6:55
Oh dear! My fault! I simply made a typo (\backrefS* instead of \backref*) and I was too tired to notice it... Thanks so much and sorry for wasting everybody's time! :-P –  Stefano Bragaglia Apr 11 '13 at 7:11
You don't need to copy all the entries from publications.bib, \bibliography{biblio,publications} in the appendix should suffice. –  mafp Jun 19 '13 at 9:40
@cyberSingularity Based on the feedback, your comment is the answer here, at least for the MWE. Could you convert to an answer? –  Joseph Wright Aug 3 '14 at 11:35

For your main question about disabling the back references for the "publications" bibliography but enabling them for the main bibliography, you can simply set the backref macros to do nothing inside the TeX group for the first bibliography (these are the macros \backrefcitedsinglestring and \backrefcitedmultistring):

\documentclass{scrreprt}

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

\usepackage[square,numbers,sort&compress]{natbib}
\usepackage[resetlabels]{multibib}
\newcites{publications}{\null}

\usepackage[pdftex]{hyperref}
\usepackage[hyperpageref]{backref}
\usepackage{bookmark}
\usepackage{relsize}

\newcommand{\backrefnotcitedstring}{\relax} %(Not cited.)
\newcommand{\backrefcitedsinglestring}[1]{\\\textsmaller{(Cited on page~#1)}}
\newcommand{\backrefcitedmultistring}[1]{\\\textsmaller{(Cited on pages~#1)}}
\renewcommand{\backreftwosep}{ and~} % separate 2 pages
\renewcommand{\backreflastsep}{, and~} % separate last of longer list
\renewcommand*{\backref}[1]{}  % disable standard
\renewcommand*{\backrefalt}[4]{\ifcase #1 \backrefnotcitedstring \or \backrefcitedsinglestring{#2} \else \backrefcitedmultistring{#2} \fi}

\begin{document}
\chapter*{Publications}
Some ideas and figures have previously and partially appeared in \citeppublications{me2012a,me2012b}.
\begingroup
% disable backref here
\renewcommand{\backrefcitedsinglestring}[1]{}%
\renewcommand{\backrefcitedmultistring}[1]{}%
% end changes added by cyberSingularity
\let\clearpage\relax
\vspace{-6ex}
\nocitepublications{*}
\bibliographystylepublications{abbrvnat}
\bibliographypublications{publications}
\endgroup

\chapter{Introduction}
In this thesis I take some of the concepts that I introduced in \citep{me2012acopy,me2012bcopy} and I quote others proposed in \citep{he2011,she2011,them2011}.

\appendix
\bibliographystyle{abbrvnat}
\bibliography{biblio}
\end{document}


(You were also missing the relsize package in your MWE.)

Your "bonus question" is sufficiently different that it warrants its own question with an appropriate title.

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