MAP20071501145 Evans, Philip Getting real about virtual commerce / by Philip Evans and Thomas S. Wurster Navigation as a separate business -- Competing on reach -- Competing on affiliation -- Competing on richness -- The Incumbent's dilemma En: Harvard business review. - Boston. - November-December 1999 ; p. 85-94 1. Comercio electrónico . 2. Internet . 3. Ventaja competitiva . 4. Marketing . 5. Empresas . I. Wurster, Thomas S. . II. Title. III. Título: Harvard Business Review.