1. Biot response spectrum;Trifunac;Soil Dynam Earthq Eng,2006
2. 70th anniversary of Biot spectrum;Trifunac;ISET J Earthq Technol,2003
3. Elastic response spectrum: a historical note;Chopra;Earthq Eng Struct Dynam,2007
4. Early history of the response spectrum method;Trifunac;Soil Dynam Earthq Eng,2008
5. Brief history of computation of earthquake response spectra;Trifunac;Soil Dynam Earthq Eng,2006