APEX DCO⁺(5−4) spectra towards the prestellar cores (top row) and protostellar cores (bottom row) in our sample. Hyperfine structure fits to the lines are overlaid in green. While the velocity range shown in each panel is the same, the intensity range is different to better show the line profiles. A double-peaked profile with a stronger red peak is detected towards IRAS 05399. The red, vertical dashed line in the IRAS 05399 panel shows the systemic velocity derived from C¹⁷O(2−1) by Miettinen et al. (2012).