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These are two of the first shoujo manga released in English, both are compilations with at least one story by Moto Hagio (A, A' is entirely by her, whereas in Four Shoujo Stories only one is, but it's by far the best one). I really can't recommend these enough if you're looking for some historical context on the shoujo genre, or break away from the vapid cliches that riddle most of the genre today.
Both these compilations of shoujo manga are emotionally mature, have a mixture of science fiction and drama, and contain at least one story by Moto Hagio. If you're tired of high-school, romantic comedies, and various other staples of shoujo, you may want ot check out these more nuanced offerings.