TY - JOUR T1 - Covariance function of a bivariate distribution function estimator for left truncated and right sensored data A1 - Gijbels, I. A1 - Gurler, U. JA - Statistica Sinica Y1 - 1998 VL - 8 SP - 1219 EP - 1232 N1 - made it ISI ER -