Enhanced <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:mi>J</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:mi>ψ</mml:mi></mml:math>-pair production from double-parton scatterings in nucleus–nucleus collisions at the Large Hadron Collider
Physics letters. B