l’errore me lo d\`a in questo file .bbl quando compilo il file .tex con pdflatex:
`
\begin{thebibliography}{1}
\bibitem{Nobre_2d}
F.D.Nobre.
\newblock Phase diagram of the two-dimensional $\pm$ J Ising spin glass.
\newblock {\em Physical Review E}, 64:046108, 2001.
\bibitem{Montecarlo_3d}
A.P.~Young H.G.~Katzgraber, M.~Körner.
\newblock Universality in three-dimensional ising spin glasses: A Monte Carlo
study.
\newblock {\em Physical Review B}, 73:224432, 2006.
\bibitem{WB_Ising}
F.D.Nobre O.R.Salmon, B.T.Agostini.
\newblock Ising spin glasses on Wheatstone–Bridge hierarchical lattices.
\newblock {\em Physics Letters A}, 374:1631–1635, 2010.
\end{thebibliography}
`
e mi dice:
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[PDFLaTeX] finished with exit status 1
./riassunto.bbl:5:Missing $ inserted …ck Phase diagram of the two-dimensional \pm
./riassunto.bbl:6: Command \em invalid in math mode on input line 6.
./riassunto.bbl:6:Command \itshape invalid in math mode. \newblock {\em
./riassunto.bbl:7:Missing $ inserted
./riassunto.bbl:7:Missing } inserted
./riassunto.bbl:4:Underfull \hbox (badness 10000) in paragraph
./riassunto.bbl:7:Extra }, or forgotten \endgroup
[PDFLaTeX] 5 errors, 1 warning, 1 badbox
`
che vuol dire?