Tanktalus, Thanks for your code and the instructions are great.
As i mentioned earlier, I need to sort the lines that start with "<ref" and with in the <address>...</address> range. Though your code sorts, it is not checking the range <address>...</address>. i.e. if the data contains 
<ref refid="aff2">2</ref>
<ref refid="aff1">1</ref>
<address>
<state>address1</state>
<ref refid="aff1">1</ref>
<ref refid="aff2">2</ref>
<ref refid="e2"/>
<ref refid="e4"/>
<ref refid="aff4">4</ref>
</address>

[download]
the first two "<ref"s outside <address> is also getting sorted.

In reply to Re^2: difficulty in sorting by texuser74
in thread difficulty in sorting by texuser74

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