I have three 1969 blondes in their original blue cord dresses. While they are the "same" doll, their hairstyles, dresses, and even shoes are slightly different. Seeing them together makes their subtle differences more obvious. Dagmar is on the left, Devereux is in the middle, and Dolores is on the right.
They can be easily identified by their hair: Dagmar has choppy bangs and a side part; Devereux has long, thick bangs; and Dolores has short, even bangs.