University of North Carolina officials reportedly contacted three other schools in the wake of committing NCAA violations in the form of 13 football players selling shoes given to them as part of UNC's apparel deal with Jordan Brand.

According to ESPN.com's Darren Rovell and Nick DePaula, North Carolina reportedly spoke with officials from Michigan, Marquette and California after it found that players from those schools may have sold shoes to the same retailer as the North Carolina football players.

The 13 UNC players were suspended Monday for between two and four games each for their role in the sales.

Shoe-marketplace site StockX confirmed to ESPN that pairs of player-issued Air Jordans were available for sale online with Michigan having the most available at 23.

Michigan football spokesman Dave Ablauf said the shoes for sale could be ones that were issued to executives and celebrities rather than players.

He also noted that players are asked to sign forms confirming that their eligibility could be adversely impacted if they sell the shoes they're given.

Air Jordans issued to athletes can sell for thousands of dollars on the open market.

Spokespersons from Michigan, Marquette and California confirmed to Rovell and DePaula that they were contacted by North Carolina and are investigating the situation.