Radio spectra for different type III/II radio-associated cases: a), b) events of 22 November 1998 and 19 December 2002 for which the type II radio burst precedes the start of the type III; in these cases the type III emanates from the type II; c) event of 18 June 2000, the type III precedes the type II radio burst and we cannot argue that the type III emitting electrons are accelerated by the shock wave. In each panel, the vertical blue lines have the same meaning as in Fig 1.