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a Quarterly rates and trend lines for quarters in 1990–2009 period for low birth weight (purple), preterm births (green), and infant mortality (orange) in Madrid with the quarter of the train bombings marked with the vertical line. b Quarterly rates and trend lines for quarters in the 1990–2009 period for low birth weight (purple), preterm births (green), and infant mortality (orange) in Spain with the quarter of the train bombings marked with the vertical line.
