# Use only some entries of a bbl file?

I have a big .bbl file which I cannot easily convert to a .bib.

Inside a new .tex file, I would like to use (cite) only few entries of the .bbl file with the help of \cite command and the label (present in the bbl).

Is it possible?

Precision: In fact, I have 300+ .tex file which contain each some references (called with \cite). There was a .bib at the origin but I have only access to the .bbl now. The .bbl contains several hundred of reference; this is why it is not really an option to copy/paste the references needed.

Here is a sample of the .bbl

\begin{thebibliography}{396}
\expandafter\ifx\csname natexlab\endcsname\relax\def\natexlab#1{#1}\fi
\expandafter\ifx\csname url\endcsname\relax
\def\url#1{\texttt{#1}}\fi
\expandafter\ifx\csname urlprefix\endcsname\relax\def\urlprefix{URL }\fi
\input{babelbst.tex}
\newcommand{\Capitalize}[1]{\uppercase{#1}}
\newcommand{\capitalize}[1]{\expandafter\Capitalize#1}

\bibitem[{Bruns(1888)}]{BruH1888}
Bruns, H.
\newblock {\"Uber die Integrale des Vielk\"orper-Problems}.
\newblock \emph{Acta mathematica} 11,  1888, 25--96.

\bibitem[{G\'erard \bbletal{}(1972)G\'erard, Reeb \bbletal{}}]{PaiP1972a}
G\'erard, R., Reeb, G., \bbland{} Sec, A., \bbleds{}.
\newblock \emph{{{\OE}uvres de Paul Painlev\'e, Volume 1}}.
\newblock Paris: CNRS, 1972.

\bibitem[{G\'erard \bbletal{}(1974)G\'erard, Reeb \bbletal{}}]{PaiP1974}
---.
\newblock \emph{{{\OE}uvres de Paul Painlev\'e, Volume 2}}.
\newblock Paris: CNRS, 1974.

\bibitem[{G\'erard \bbletal{}(1975)G\'erard, Reeb \bbletal{}}]{PaiP1975}
---.
\newblock \emph{{{\OE}uvres de Paul Painlev\'e, Volume 3: \'Equations
diff\'erentielles du second ordre}}.
\newblock Paris: CNRS, 1975.
.
.
.
\end{thebibliography}

• You have not given much information, But in most bbl markup you should be able to simply delete the entries that you do not use. It is unusual to have a .bbl file not generated by bibtex, is there really no .bib source available? (hand written bibliographies have no reason to use that .bbl extension.) – David Carlisle Mar 28 at 17:17
• Are you using biblatex as suggested by the tags? It would be possibly to some limited degree to make use of a pre-existing .bbl file (assuming refcontexts and refsections match), but that is very fragile and crucially relies on the .bbl version matching with your biblatex version. Since the .bbl may contain additional (variable) information not present in the .bib (for disambiguation, mainly) it can not be guaranteed that things will look alright when you only select a subset of the entries and ignore the rest. – moewe Mar 28 at 20:55
• It would help if you could share more details about your .bbl file, your general setup and what you have in mind. – moewe Mar 28 at 20:55
• This .bbl file was created by BibTeX for standard thebibliography inclusion and is therefore completely incompatible with biblatex. Do you want to use it with biblatex? – moewe Mar 28 at 21:09
• I would have thought it would be a simple job to just use an editor or perl or whatever, just run latex without the bbl file so latex writes the citation keys to the aux file (which is what bibtex would use) then just extract that list of entries from the bbl file. – David Carlisle Mar 28 at 22:16