& @entrances
 
  Syntax: @entrances [[<object>][,<low>[,<high>]]]
 
  Lists links from elsewhere to the specified object (default: your
  current room).  For rooms, exits and drop-to's, leading to the 
  room and players and objects whose home is in the room are listed.  
  For players and objects, lists exits leading to them.  Because 
  this command is computationally expensive, it costs 100 coins.  
  <low> and <high> can be used to indicate where to start and stop 
  the search, respectively.
 
  Examples:
    > @entrances             <- all links to here
    > @entrances object      <- all links to object
    > @entrances ,100,200    <- all links to here from #100 to #200
    > @entrances me,1000     <- all links to me from #1000 and above.
 
  See also: @link, @unlink