First Observations of Y(1S) → γπ+π- and Y(1S) → γπ0π0 - 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)