Side note: you don't normally need a & in front of a subroutine name anyhow. In fact, adding one changes the semantics slightly. But the thing to read is the following excerpt from le manpage du jour, perldoc perlop:

 "`->'" is an infix dereference operator, just as it is in
       C and C++.  If the right side is either a `[...]',
       `{...}', or a `(...)' subscript, then the left side must
       be either a hard or symbolic reference to an array, a
       hash, or a subroutine respectively.  (Or technically
       speaking, a location capable of holding a hard reference,
       if it's an array or hash reference being used for
       assignment.)  See the perlreftut manpage and the perlref
       manpage.

       Otherwise, the right side is a method name or a simple
       scalar variable containing either the method name or a
       subroutine reference, and the left side must be either an
       object (a blessed reference) or a class name (that is, a
       package name).  See the perlobj manpage.
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Most modules use the standard Exporter module, which provides a standardized import mothod, although you are free to write your own. Read perldoc Exporter and poke around in a few of your favorite modules to see how Exporter gets used.

HTH

perl -e 'print "How sweet does a rose smell? "; chomp ($n = <STDIN>); 
+$rose = "smells sweet to degree $n"; *other_name = *rose; print "$oth
+er_name\n"'
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