Exodus 28:31
And thou shalt make the robe of the ephod wholly of blue;
Exodus 28:4
These, therefore are the garments which they shall make - a breastpiece, and an ephod and a robe, and a tunic of checker work, a turban and a girdle, - so shall they make holy garments for Aaron thy brother and for his sons, for ministering as priests unto me.
Exodus 28:28
that they may bind the breastpiece by the rings thereof unto the rings of the ephod with a cord of blue, so that it may remain upon the curious band of the ephod, and the breastpiece not be removed from of the ephod.
Exodus 39:22-26
And he made the robe of the ephod, the work of a weaver, wholly of blue;
Leviticus 8:7
and put upon him the tunic and girded him with the band, and clothed him with the robe, and put upon him the ephod, and girded him with the curiously-woven band of the ephod, and bound it to him therewith;