latex build problem

[Osamu Aoki <osamu@debian.org>]

I encounter errors in latex when building PS file (or PDF file).

I do not understand "(\end occurred inside a group at level 31)"

What should I look for for this error?  I tried "-v" option in
debiandoc2latexpsand essentially same output with pool size.

I have big enough pool size and error messages are as follows
.....
Appendice A.
[177] [178]
Underfull \hbox (badness 4899) in paragraph at lines 9373--9375
[]\T1/ppl/m/n/10.95 I fi-les SGML ori-gi-na-li usa-ti per crea-re il do-cu-men-
to so-no di-spo-ni-bi-li in CVS pres-

Underfull \hbox (badness 5359) in paragraph at lines 9373--9375
\T1/ppl/m/n/10.95 so: \T1/pcr/m/n/10.95 :pserver:anonymous@cvs.qref.sf.net/cvsr
oot/qref \T1/ppl/m/n/10.95 op-pu-re [][]$\T1/pcr/m/n/10.95 http : / / qref .
[179]
Underfull \hbox (badness 1122) in paragraph at lines 9384--9386
[]\T1/ppl/m/n/10.95 Le uti-li-t^^e0 per la con-ver-sio-ne da De-bian-Doc SGML s
o-no di-spo-ni-bi-li nel pac-chet-to De-bian
[180] (./reference.it.aux)

LaTeX Warning: Label(s) may have changed. Rerun to get cross-references right.

 )
(\end occurred inside a group at level 31)
(see the transcript file for additional information)
Output written on reference.it.dvi (184 pages, 443988 bytes).
Transcript written on reference.it.log.
debiandoc2latexps: ERROR: reference.it.dvi could not be generated properly

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        Osamu Aoki <osamu@debian.org>   Cupertino CA USA, GPG-key: A8061F32
 .''`.  Debian Reference: post-installation user's guide for non-developers
 : :' : http://qref.sf.net and http://people.debian.org/~osamu
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