where is mit-scheme?

[Peng Yu]

According to the package search webpage, mit-scheme is shown under
'devel'. Is it the reason that I can not install mit-scheme?

$ sudo apt-get install mit-scheme
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package mit-scheme 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
However the following packages replace it:
  mit-scheme-doc
E: Package mit-scheme has no installation candidate

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Package mit-scheme

    * karmic (devel): MIT/GNU Scheme development environment [universe]
      7.7.90+20090107-1ubuntu1: i386

Other hits
Package mit-scheme-dbg

    * karmic (devel): MIT/GNU Scheme debugging files [universe]
      7.7.90+20090107-1ubuntu1: i386

Package mit-scheme-doc

    * karmic (doc): MIT/GNU Scheme documentation [universe]
      7.7.90+20090107-1: all