Strontium-to-iron ratios in the Galactic globular clusters and field stars. The observational data for field stars are taken from Lai et al. (2008), Ishigaki et al. (2013), Roederer et al. (2014), Battistini & Bensby (2016). The vertical black lines and the vertical red line with the horizontal line at the end show the standard deviation of the mean due to star-to-star abundance scatter. The vertical red line with dots at the end shows the minimum and maximum values.