Iceweasel browser was not running properly so I removed it from "Add/Remove Software" with one of the dependency that I can't remember.But when I tried to re-install it using apt-get install iceweasel , it is giving me following error

Reading package lists... Done
Building dependency tree
Reading state information... Done
Package iceweasel is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'iceweasel' has no installation candidate

How can I install it.