Simplicity 5066 vintage sewing pattern, dated 1960s. 

Misses' One-Piece Jiffy Dress:

Simple to Make A-line dress has a high round neckline, kimono-style sleeves and back zipper closing. V 1 features 3/4 length sleeves and a self-fabric tie belt worn below waistline and held in place with 2 thread loop carriers. V 2 has short sleeves and is detailed with top-stitching.

Size  12:

Bust  32 inches / 81 cm

Waist 25 inches / 64 cm

Hip    34 inches / 86 cm

Pattern is UNPRINTED, checked complete. Envelope has some small tears around top.

More '60s patterns here:

http://allthepreciousthings.com/collections/1960s