The mass parameter of dilaton space-times is obtained as a function of the redshift-blueshift (zred, zblue) of photons emitted by particles orbiting in circular motion around these objects and their corresponding radii. Particularly, we work with the generalized Chatterjee and Gibbons- Maeda space-times. Both of them become the Schwarzschild black hole in certain limit of one of their parameters. Bounds for the values of these frequency shifts, that may be observed for these metrics, are also determined.
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