Data:L10a81/PD Presentation

X₈₁₉₂ X_12,3,13,4 X_14,19,15,20 X_16,5,17,6 X_18,10,19,9 X_4,15,5,16 X_10,18,11,17 X_20,13,7,14 X₂₇₃₈ X_6,11,1,12