Abundance ratios [La/Fe] versus [Nd/Fe]. Error bars are also plotted. The symbols are the same as in Fig. 1. Here, r-rich stars (filled stars, including seven r-II stars and three r-I stars) are also presented for comparison. The r-rich stars are taken from the sample collected by Cui et al. (2013b, and references therein). The lines represent the solar [La/Nd] values: dotted for solar s, dashed for solar r, and solid for solar normal. (See color version online.)