"Within a year he Doge Pietro Orseolo II had negotiated with Basil II in Constantinople commercial terms more favourable than any that Venice had previously enjoyed. An imperial chrysobul dated March 992 undertook to admit bona fide Venetian goods – though not those from other sources carried on Venetian ships – at tariffs far lower than those imposed on foreign merchandise in general."
– John Julius Norwich, A History of Venice (London: Penguin, 2003; orig. pub. 1982), p. 50.