Duke University is a private research university in Durham, North Carolina. Founded by Methodists and Quakers in the present-day town of Trinity in 1838, the school moved to Durham in 1892.
The President is said to have discussed the idea of purchasing Greenland, an autonomous Danish territory, during dinners and meetings with advisers.
But Greenland's government dismissed the idea, saying: "We're open for business, not for sale. "
Mr Trump's plans have also been quickly dismissed by politicians in Denmark. tweeted former Prime Minister Lars Lokke Rasmussen.
The Wall Street Journal (WSJ), which first reported the news,
Sources quoted in other media differed over whether The President was joking or seriously hoping to expand US territory.How has Greenland reacted?
Officials in Greenland have insisted that The Island is not on the market.
"Greenland is rich in valuable resources such as minerals, the purest water and ice, fish stocks, seafood, Renewable Energy and is a New Frontier for adventure tourism. We're open for business, not for sale," The Foreign ministry said in a statement shared on Social Media .
Greenland Premier Kim Kielsen repeated the comments in a separate statement. "Greenland is not for sale, but Greenland is open for trade and cooperation with other countries, including the USA," he said.
Greenland MP Aaja Chemnitz Larsen
"No thanks to Trump buying Greenland!", she wrote on Twitter, adding that a "better and more equal partnership with Denmark" was the way forward.
Poul Krarup, editor-in-chief of Greenland's Sermitsiaq newspaper, told the BBC he "couldn't believe" Mr Trump's remarks.
"Greenland is an independent area in the Danish kingdom and must be respected as such," he said.
But he said he thought the chances of Mr Trump's reported ambitions being realised were Unlikely .
Politicians in Denmark have ridiculed the idea of a possible US acquisition.
"If he is truly contemplating this, then this is final proof, that he has gone mad," foreign affairs spokesman for the populist Danish People 's Party, Soren Espersen, told national broadcaster DR.
"The thought of Denmark selling 50,000 citizens to the United States is completely ridiculous. "
She is set to visit Greenland this weekend and has said she is "very much Looking Forward " to it.
Mr Trump is scheduled to visit Denmark in September but there is no indication that the possible acquisition of Greenland is on The Agenda .
The WSJ reported that it was "unclear" how the US would go about acquiring Greenland if Mr Trump was serious.Where is Greenland?
Greenland is the largest island in The World (after Australia, which is defined as a continent in its own right). It is an autonomous Danish territory, located between the North Atlantic and Arctic oceans.
But it's also believed that the receding ice may expose toxic nuclear waste that was left at several US military sites during the Cold War .Why would it be appealing to Trump?
Mr Trump has reportedly taken an interest in Greenland, in part, because of its natural resources, such as coal, zinc, copper and Iron Ore .
But while Greenland might be rich in minerals, it currently relies on Denmark for two thirds of its budget revenue. It has high rates of suicide, alcoholism and Unemployment .Reports differ over whether Mr Trump was serious about trying to purchase Greenland
Republican Representative Mike Gallagher
"The United States has a compelling strategic interest in Greenland, and this should absolutely be on the table," he tweeted.Can countries buy territories?
Historically, countries have acquired territory not only through military conquest but also financial deals.
Under the 1803 Louisiana Purchase , the US acquired about 827,000 sq miles (2. 1m sq km) of land from France for $15m (£12. 3m). In 1867, the US reached a deal with Russia to purchase Alaska for $7. 2m.
The US later purchased the Danish West Indies in 1917 and renamed them the US Virgin Islands.
"I think in part because nations can often get what they want without expanding their sovereign territory, and also because. . People can't Just Be bartered around like chattel anymore," said Professor Blocher.
In 1867, suggested that Greenland's strategic location, along with its abundance of resources, made it an ideal acquisition.
But no official move was made until 1946, when Harry Truman offered Denmark $100m for The Territory .
He had earlier toyed with the idea of swapping land in Alaska for strategic parts of Greenland, according to AP.