hardness of your , 40_MAT_19_08 , hardness of your , 41_MAR_10_05 ,
 the hardness of , 40_MAT_19_08 , the hardness of , 41_MAR_03_05 ,
 the hardness of your , 40_MAT_19_08 , the hardness of your , 41_MAR_10_05 ,
 for the hardness , 41_MAR_03_05 , for the hardness , 41_MAR_10_05 ,
 for the hardness of , 41_MAR_03_05 , for the hardness of , 41_MAR_10_05 ,