* Anil K. Chopra, "Dynamics of Structures - Theory and applications to Earthquake Engineering", Pearson Education Asia Limited and Tsinghua University Press, Beijing, 2001* Leonard Meirovitch, "Elements of Vibration Analysis", Mc-Graw Hill Inc., Singapore, 1986==External links==*Duhamel's formula at "Dispersive Wiki".
* Anil K. Chopra, "Dynamics of Structures - Theory and applications to Earthquake Engineering", Pearson Education Asia Limited and Tsinghua University Press, Beijing, 2001* Leonard Meirovitch, "Elements of Vibration Analysis", Mc-Graw Hill Inc., Singapore, 1986*Duhamel's formula at "Dispersive Wiki".