Friswell, M., Adhikari, S., Friswell, M., & Adhikari, S. (2010). Distributed parameter model updating using the Karhunen–Loève expansion. Mechanical Systems and Signal Processing, 24(2), pp. 326-339. doi:10.1016/j.ymssp.2009.08.007

Friswell, Michael, S. Adhikari, M.I Friswell, and Sondipon Adhikari. "Distributed Parameter Model Updating Using the Karhunen–Loève Expansion." Mechanical Systems and Signal Processing 24, no. 2 (2010): 326-339.

Friswell, Michael, S. Adhikari, M.I Friswell, and Sondipon Adhikari. "Distributed Parameter Model Updating Using the Karhunen–Loève Expansion." Mechanical Systems and Signal Processing 24.2 (2010): 326-339.