This pattern is from the book Blueprint Crochet which is available in print and eBook form. It is also available as a single pattern download from the Interweave Store.

Yarn: Sport-weight (#2 Fine)
Shown: Chelsea by Lily Chin Signature Collection
(30% Merino Wool, 35% Cotton, 35% Acrylic; 191 yd 174.5 m/1.75 oz 50 g): #5811 light blue, 7 (9, 11, 13) balls.
Hooks: H/8 (5.0mm) and G/6 (4.25mm) or hooks needed to obtain gauge.
Notions: Tapestry needle; 4 (4, 5, 5) 3/8” (1 cm) black pearl buttons.
Gauge: 3¼ x 3¼“ (8.5 x 8.5 cm) =Granny Motif with smaller hook
35/8” x 35/8”” (9.5 x 9.5 cm) = Granny Motif with larger hook
Size: Small, (Medium, Large, X-Large) fits 34 (38, 40, 44)“ (86.5 96.5, 102, 112 cm) bust circumference. Finished bust measures 32½” (36¼“, 39”, 43½”) (82.5 92, 99, 110.5 cm).
Sweater is shown in size Small.