Activists and industry groups pitted against each other in the debate have no shortage of studies they can invoke as ammunition.

FORBES: Connect

While Murray has said he would invoke his Fifth Amendment rights to avoid testifying as his criminal appeal is pending, Dr. Finkelstein is expected to take the stand.

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Parties invoke the Convention in different contexts and manners, such as by participating in meetings and conferences, within the framework of cultural or trade agreements.

UNESCO: Cultural Expressions

The sovereignty of the United States resides in the people, and Congress cannot invoke the sovereignty of the people to override their will as declared in the Constitution.

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As for art as a leading indicator, whose art do you invoke?

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Specifically, the issue is whether Congress can invoke its Commerce Clause power to compel individuals to buy insurance as a condition of lawful citizenship or residency.

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Less satisfying is his account of California's cultural progress in the 19th and 20th centuries: does he really need to invoke so many long-forgotten writers to accompany such names as Jack London, Frank Norris, Mark Twain or Raymond Chandler?

ECONOMIST: California

At sentencing, it is common for defense counsel and judges alike to invoke the passage of time and intervening efforts by the cooperating witness to acknowledge his or her wrongdoing as factors in favor of a reduced sentence.

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Many invoke the cautionary tale of Mr Kerry, the Democratic nominee in 2004, who found his supposed strength as a war hero turned into a liability by ads suggesting he had lied about his conduct in Vietnam.

ECONOMIST: Lexington