NH₃ (1,1) and (2,2) line widths with their errors. The red line marks equal widths. The warm-starless, prestellar, and protostellar cores are indicated with squares, circles, and stars, respectively. The colours represent the areas where the cores are from (see Fig. 1). The filled points mark the reliable sample, the open points the candidate sample. The point that has a (2,2) FWHM of 5.15 km s⁻¹ has been excluded from further analysis based on its broad line width.