This design was in the Autumn 2017 Rowan newsletter.

You will need a cable needle and 5 buttons. Rowan used style G440428 from Groves & Banks

Finished measurements:
Back width: 17 (19, 21, 23, 25)”; 43 (48, 53, 58, 63) cm
Total length: 17 (17.5, 18.5, 19.5, 20)”; 43 (45, 47, 49, 51) cm
Sleeve length to underarm: 13 (13, 13.5, 13.5, 13.5)”; 33 (33, 34, 34, 34) cm

Yarn used:
Rowan Cashmere Tweed
Shade 005 Cinder Rose - 11 (13, 14, 15, 17) balls