It would be the start of a war of unknown duration and immense human, material, and political cost.
As the American involvement in Iraq has become a commitment of unknown duration, comparisons to the Vietnam War are more and more common.
But industry analysts said that the drug companies faced a battle to expand the target audience in America for such vaccines because the drugs have limited effectiveness and unknown duration.
The conglomerate that begins the Bruce is separated from pre-Huronian schists by a profound erosional surface representing a time span of unknown duration.
"Without prejudging the outcome of mechanistic studies being written up for publication," he wrote, "it is entirely possible that granting your request could entail a delay of unknown duration with no public discussion or review of the strong new studies that are now available".
Bafflingly assigned to a Saturday slot following three Wimbledon finals of unknown duration, with rain forecast several days ahead, the starry, costly and heavily promoted production of Henry IV Part 1 predictably had to be postponed during the tennis to 10pm, so that it ended at midnight ("no notice, rubbish scheduling", tweeted Polly Toynbee).
[C1.] An Uncertain Future for Media in New Orleans New Orleans media outlets, including The Times-Picayune and seven television stations, have been left to contemplate a surreal future of unknown duration in a city void of functioning businesses, with no goods to advertise and almost no people to buy them.
They offered Queequeg and myself positions as sailor-developers, for a voyage of unknown duration, into treacherous, uncharted waters.
In this paper we present a strategy to route unknown duration virtual circuits in a high-speed communication network.
