Pairs of O−C plots for both components of candidate binary double Cepheids. The LTTE fit is shown with a red line for systems with a correlation parameter of O−C variations of r < −0.8. Three systems (OGLE-SMC-CEP-1526,3115,3674) show very strong evidence for LTTE. Two other stars (OGLE-LMC-CEP-0835,0571) show anticorrelated phase shifts, but the conclusions are less clear (see text). We show a common orbital solution for them in Fig. 3.