I find changing $/ to be too confusing. That's not to say that it can't be used to good effect, only that it's easier to read usually when you don't. So, here goes: 

#! /usr/bin/perl -w

use strict;

my @sortable;
while ( <DATA> ) {

    # are we in the ref's?
    if (/^\<ref/)
    {
        # keep track of it, but don't print it out yet.
        push @sortable, $_;
        next;
    }
    
    # else, are we done ref's?
    if (@sortable)
    {
        print for sort @sortable;
        # done with them, get rid of 'em.
        @sortable = ();
    }

    # this line can be printed out at this point.
    print;
}


__DATA__
[ same as yours, so I'm not repeating it ]

[download]
It seems to get the job done. Of course, I'm assuming that all the ref lines are in a row.

In reply to Re: difficulty in sorting by Tanktalus
in thread difficulty in sorting by texuser74

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