The legend for Figure 1 (p. 474) of the article by Stempfel et al. (Pediatrics, 17:471, 1956) should have read:
Fig. 1. Effect of exchange transfusions on the concentrations of bilirubin in the sera of patients with hemolytic disease of the newborn: a) without biliary obstruction, and b) with biliary obstruction. Broken lines at 200 mg./100 ml. represent "critical" levels.