Specific targeting with polyethylene glycolj-modified liposomes: coupling of homing devices to the ends of the polymeric chains combines effective target binding with long circulation times - Blume, G; Cevc, G; Crommelin, D J; Bakker-Woudenberg, I A J M; Kluft, C; Storm, G (Biochim Biophys Acta, 1993)