Mysterious Note

There are two "Mysterious Notes" in The Elder Scrolls V: Skyrim:

Mysterious Note from Delphine

Mysterious Note
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Type	Book
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ID	0003031f

A letter from the Blades to the Dragonborn.

Found

• Ustengrav where the Horn of Jurgen Windcaller should have been.

Content

Mysterious Note from the Dark Brotherhood

Mysterious Note
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Type	Book
Weight	0
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ID	0005224a

Message from the Dark Brotherhood.

Found

• Delivered to the Dragonborn by courier after Grelod the Kind has been killed.

Content

Notes

• Apparently on finding the former, the latter will not be sent to the Dragonborn via courier, thus making it a bit confusing to begin With Friends Like These….