Sisters Mary Lomax and Bonnie Loggins are aged 86 and 93, respectively, but as public performance goes, they're rookies. In fact, they didn't sing in front of an audience until they were into their ninth decade on earth. The sisters' specialty is unaccompanied Appalachian balladry, a lost art of sorts featuring centuries-old songs learned during family singalongs decades ago and which local artist, musician, writer and folk historian Art Rosenbaum has chronicled in his new book, The Mary Lomax Ballad Book: America's Great 21st Century Ballad Singer. It goes without saying there aren't many chances left to witness this sort of performance, but I've got a word count to fill, so there you go. Loggins' son Casey and fiddler Roy Tench, himself a spry and talented nonagenarian musician, will also appear, and copies of Rosenbaum's book will be available at the ensuing reception.