Maestro n° 102 : Page 84 - Gr 81
L1C7 =6=7= L1C7 -7- L9C7 =7=8= L9C7 -8- L9C3 =8= L2C3 -8- L1C1 =8= L1C6 -8-9- L1C6 =9= L1C4 -9-6- L1C4 =6= L3C5 donc L1C4 et L3C8 ≠ 6