First observations of Y(1S)->gamma pi(+)pi(-) and Y(1S)->gamma pi(0)pi(0) - Anastassov, A; Duboscq, J; Gan, K; Hart, T; Honscheid, K; Kagan, H; Kass, R; Lee, J; Schwarthoff, H; Wolf, A; Zoeller, M; Richichi, S; et al. (1999)