We study positive blowing-up solutions of systems of the form:
with
b4078923a5c" title="Click to view the MathML source">δ1,δ2>0 and
p,q>0. We prove single-point blow-up for large classes of radially decreasing solutions. This answers a question left open in a paper of Friedman and Giga (1987), where the result was obtained only for the equidiffusive case
δ1=δ2 and the proof depended crucially on this assumption.