The PLRs at K_s for classical Cepheids in the SMC (left) and LMC (right) (grey dots and filled lines, see Appendix A). Also shown for comparison are the relations for the T2Cs, indicated by dashed lines. Symbols for the T2Cs are the same as in Fig. 2 except the crosses in the LMC sample which indicate stars not used in the least-squares fits (see M09). RVs and pWs are shown as open circles and squares.