Color excesses of classical cepheids. I The color excesses of eleven cepheids have been determined with the aidof photometry of field stars found in the proximity of the variables. Acomparison of the color excesses with previous color-excess results isgiven. Four cepheids: RT Aur, DT Cyg, Zeta Gem, and T Vul, haverelatively small and well-established reddening values. These fourstars, along with Alpha UMi, can serve as standards to calibratereddening-free indices with intrinsic color indices such as (b-y) or(B-V).
