The canonical form of a dereference is to take the normal form: 
@FOO

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and replace the word (here FOO) with a block returning the reference: 
@{$a[0]}

[download]
Only when the braces enclose a simple scalar variable (like $x) can you drop the braces. You don't have a simple scalar here, so the braces must remain on.

In reply to Re: Dereferencing Subroutine Arguments by merlyn

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