“…Many studies used additional measures to improve accuracy of the testing technique, including the use of mineral oil to lubricate the specimen-platen interface 22 , 24 , 26 , 34 , 61 , 88 , 103 , 127 - 129 , 133 , 147 , 148 , 162 and embedding the specimens in brass, aluminium alloy, or stainless-steel endcaps. 4 , 8 , 19 , 28 , 29 , 34 - 36 , 39 , 40 , 49 , 73 , 76 , 77 , 90 , 99 , 113 , 118 , 119 , 131 - 133 , 142 , 144 , 153 , 159 , 164 , 167 , 169 Some studies used latex, 33 , 38 , …”