Don't know the veracity of this site, but the caption on this image dates it to the 1960s: http://www.finest20thcentury.com/art--objects?lightbox=image_1znn She was apparently from Pittsburgh. This obituary of her husband from 2014 calls her "Pittsburgh artist, the late Maggie Milono." http://www.legacy.com/obituaries/postgazette/obituary.aspx?pid=170911316 I also found that there is an award named after her. And found something from 1996 saying a memorial exhibition was being put together in her honor.
I'm surprised, too -- she seems to have been very well regarded, at least in the Pittsburgh area if not beyond.