Data:L10n87/PD Presentation

X₆₁₇₂ X_10,3,11,4 X_11,19,12,18 X_17,9,18,8 X_7,17,8,16 X_13,15,14,20 X_15,5,16,14 X_19,13,20,12 X₂₅₃₆ X_4,9,1,10