All you have to do is
1) delete the last two lines (the ones you added a short time ago)
2) uncomment the lines that begin with deb-src
but most importantly
0) READ THE DOCUMENTATION BEFORE ASKING FOR ADVICE ON MAILING LISTS ;)
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Riccardo (Jack) Lucchetti
Dipartimento di Scienze Economiche e Sociali (DiSES)
Università Politecnica delle Marche
(formerly known as Università di Ancona)
r.lucchetti(a)univpm.it
http://www2.econ.univpm.it/servizi/hpp/lucchetti
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