Rex Energy Corp.has agreed to sell nonoperated assets in Westmoreland, Centre and Clearfield counties, PA, to privately owned XPR Resources LLC for $17.2 million. The sale is expected to close by the end of March. Included are 61 gross wells producing 8.2 MMcf/d. Rex began divesting noncore assets in 2015 to boost liquidity. The company disclosed in a regulatory filing in February that is exploring financial alternatives to strengthen its balance sheet, including the possibility of filing for bankruptcy.