Individual lower bound for Calderon's generalized Lorentz norm estimates
  We find the exact values for constants in bilateral Calderon-Stein-Weiss inequalities between tail (Marcinkiewicz) norm and weak Lebesgue (Lorentz) norm.   Possible applications: Functional Analysis (for instance, interpolation of operators), Integral Equations, Probability Theory and Statistics (tail estimations for random variables). 
E. Ostrovsky, L. Sirota
math.FA