From: Alice <alice@example.org>
To: Daniel <daniel@example.org>
Subject: leaf message
In-Reply-To: <mutant-ref-parent2@example.org>
References: <mutant-ref-parent2@example.org>
Message-ID: <mutant-ref-leaf@example.org>
Date: Thu, 16 Jun 2016 22:14:41 -0400

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