It looks like Donald Trump’s book sales got a boost from his own presidential campaign.

The Republican nominee directed $300,000 of small donors’ money to the publisher of his bestselling business book “The Art of the Deal” in the past month, according to a Monday Huffington Post review of the Trump Make America Great Again Committee’s most recent FEC report.

Trump has made a habit of funneling campaign money to his own businesses, spending tens of thousands to hold events at his properties and jacking up the monthly rent of his Trump Tower campaign headquarters once he started accepting funds from donors.

The Oct. 15 FEC filing lists three entries paid to Penguin/Random House for “Collateral: Books”; one for $91,866 on August 30, one for $98,975 on September 1, and one on $98,975 on September 22, HuffPo reported. The publishing house has printed five Trump books including “How To Get Rich” and “Think Like A Billionaire.”

While the title isn’t specified in the October filing, a promotional offer on the committee’s website indicates that the campaign is purchasing copies of Trump’s ode to deal-making.

“I’ve signed an out-of-print, hardcover copy of ‘The Art of the Deal’ just for you, because I want you on board with Team Trump!” Trump wrote in an August 2 fundraising email that offered the book for a minimum donation of $184. As HuffPo noted, the book is not actually out-of-print.

Instead, the fundraising effort allows the Trump team to sell copies of the book—which also directs royalties back to the real estate mogul—to small donors at an artificially inflated cost.

According to HuffPost, the Trump Make America Great Again Committee focuses on small-donor contributions while the joint Trump-Republican National Committee manages large donations.

Penguin/Random House and the Trump campaign did not respond to Huffington Post’s request for comment.