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[21] Notice however, that this expansion parameter is not based on the properties of the mechanical excitation itself but on the sample response to it.

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[23] According to Callen [1], a system is at equilibrium if Thermodynamics holds for such state.

[24] Notice, that in Fig. 1(c) of our previous work [26], the maximum value of Gamma reported was half of the value shown here. This discrepancy is due to a deficient filtering of the accelerometers used in Ref. [26]. The accelerations reported here have been corrected and checked against measurements done with a high speed camera.

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