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: Louet Euroflax Sportweight (100% Wet Spun Linen; 270 yd 247 m/ 3.5 oz 100 g): french blue (MC), 5 (7, 8, 10) hanks; cream (CC1), 1(1,1,1) hanks; aqua (CC2), 1(1,2,2) hanks.
Hook: US G/6 (4.25mm) or hook needed to obtain gauge
Notions: Tapestry needle; stitch markers; pins.
Gauge: 22 sts (11 SR) and 14 rows (7 RR) = 4 x 4” (10.5 x 10.5 cm) in stitch pattern
Size: Small (Medium, Large, X-Large) fits 34 (38, 42, 46)“,
(86.5, 96.5, 107, 117 cm) bust circumference. Tunic shown in a Small.