Before revision:  Since in growth on flat substrates the linear size of the system remains constant, whereas it increases in the caseof growth on curved substrates, the universality class of{\bf  [  in the long-time limit.
After revision:  Since in growth on flat substrates the linear size of the system remains constant, whereas it increases in the caseof growth on curved substrates, the universality class of{\bf , 116101, 2008) argued, however, that for the radial KPZ equations in (1+1)-dimension w(t) should increase as w(t)\sim[ in the long-time limit.