  In this paper we present a nonparametric method for extending functional
regression methodology to the situation where more than one functional
covariate is used to predict a functional response. Borrowing the idea from
Kadri et al. (2010a), the method, which support mixed discrete and continuous
explanatory variables, is based on estimating a function-valued function in
reproducing kernel Hilbert spaces by virtue of positive operator-valued
kernels.
