Two germanium resistors, C and D, have been referenced to values of temperature determined by the NBS acoustical thermometer. The resistance-temperature calibration data for these resistors have been fitted to a function of the form R = ∑ n = 0 m A n ( log 10 T ) n and the results are presented. The resistors C and D that are used as secondary standards maintain the scale, NBS Provisional Scale 2 – 20 (1965), to which public calibrations of germanium thermometers are referenced. The calibration apparatus and measurement techniques that are employed in calibrating submitted resistors are described in detail. Additionally, data of three typical calibrations and their treatment by polynomial fitting are included to demonstrate the characteristics of some commercially available germanium resistors.