aDepartment of Mechanical Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore
bDepartment of Engineering Mechanics, Southeast University, 2 Sipailou Street, Nanjing 210096, China
Abstract:
In response to the comment made by Ferrari on our previous paper [C.J. Tay, C. Quan, F.J. Yang, X.Y. He, Opt. Commun. 239 (2004) 251], we have the following clarifications to make.