updating a packages from unstable version

[Roberto Bernetti <r.bernetti@mm.univpm.it>]

Hi
I'd like to hold the stable but I need to install "maxima" that the maintener 
told me is available only in the unstable distribution. 
In order to check whether I have correctly understood the documentation 
informations, I'd check the sequence of operations to upgrade 
only the maxima package on my stable:

1) adding to the file /etc/apt/apt.conf.d/70debconf the following line:

             APT::Default-Release "stable";

2) adding to the file /etc/apt/sources.list  the following URL where is the 
maxima package
        deb-src http://http.us.debian.org/debian unstable main contribn 
on-free
        deb-src ftp://non-us.debian.org/debian-non-US unstable non-US/main  
non-US/contrib non-US/non-free

3)  now issuing ( if the package is available )
        apt-get -t unstable install maxima
otherwise 
        apt-get build-dep maxima
        apt-get source --compile maxima
        dpkg -i maxima
Thanks in advance for the time you would give me.
Best regards
Roberto
-- 
Roberto Bernetti
Dipartimento di Meccanica
Università Politecnica delle Marche
via Brecce Bianche
60131 Ancona, ITALIA
tel.: +39-071-2204542
fax.: +39-071-2204801
e-mail: r.bernetti@mm.univpm.it