Dezső Gergely;  Bálint I.;  Gyémánt Iván Károly: Inequalities relating the Elements of the Second-Order Reduced density Matrix.
   In:  Recent Advances in the Theory of Chemical and Physical Systems.   Progress in Theoretical Chemistry and Physics, 15  (15).  Springer Netherlands, Dordrecht, pp. 151-157. (2006)  ISBN 1402045271; 9789400788596; 9781402045288