sedde:/home/sedde# apt-get install nvidia-kernel-common
Reading package lists... Done
Building dependency tree... Done
Recommended packages:
  nvidia-kernel-source nvidia-kernel
The following NEW packages will be installed:
  nvidia-kernel-common
0 upgraded, 1 newly installed, 0 to remove and 1 not upgraded.
Need to get 4332B of archives.
After unpacking 53.2kB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
  nvidia-kernel-common
Install these packages without verification [y/N]? y
E: Some packages could not be authenticated