Riddell, R. Inelastic response spectrum: Early history. Earthquake engineering & structural dynamics..
Čikaški stil citiranja (17. izdanje)Riddell, Rafael. "Inelastic Response Spectrum: Early History." Earthquake Engineering & Structural Dynamics. .
MLA način citiranja (9. izdanje)Riddell, Rafael. "Inelastic Response Spectrum: Early History." Earthquake Engineering & Structural Dynamics., .
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