Huge amounts of detective work would be needed to find out who they were.
George Osborne, the chancellor, said that "a great deal of detailed work" would be needed before the proposals became law.
Despite their findings, the researchers suggested that much more work would be needed to understand the likely effects of a sunlight management strategy on agriculture.
However, Beckham's response would indicate some work would be needed: "Tom's not offered any acting lessons yet or parts," Beckham said.
However, it also carried risks beyond the potential gas leaks, including the possibility that more work would be needed or that there would be delays, the document said.
Mr Kerry cautioned that, if implemented, the deal would only achieve a "pause" in fighting and that more work would be needed to reach a full ceasefire.
An analysis of the library found that if it was expanded much work would be needed to bring the building up to meet new codes.
But he added that company officials and the commission staff had not yet determined what kind of work would be needed to demonstrate the structure's safety.
It is a credible project, but years of development work would be needed to turn it into a commercial reality, and it would be unlikely to enter service before 2030.
Jouty expected the first basic analysis in "a matter of days" but warned this read-out could be subject to errors and that more work would be needed for a full interpretation.
Officials on both sides predicted that the divisions would continue and that hard work would be needed to resolve them — adding to the challenges of the country, which is now part of the European Union but has faced severe economic trouble since the financial crisis of 2008.
