Letter from Duke Abele is a note found in Dishonored 2.
Kirin, my dear Grand Inventor!
Who else possesses such a keen mind? Could any other of my inner circle achieve such industrial marvels?
I appreciate how superbly your Clockwork Soldiers performed in Dunwall, cutting those guards loyal to Emily Kaldwin to ribbons. And Breanna Ashworth claims you've been invaluable, helping her Oraculum contraption. Delilah will be pleased.
Please dispatch a courier as soon as you have what you need from Anton Sokolov. Press him as you see fit. No methods are off limits! We must find a way to produce your Clockwork Soldiers in greater quantities.
The note can be found on the desk inside Jindosh's bedroom during the mission The Clockwork Mansion.