2               Tensor2<double, 3, 3> &t2_1, 
const Tensor2<double, 3, 3> &t2_2,
 
    3               Tensor2_symmetric<double, 3> &t2s_1,
 
    4               const Tensor2_symmetric<double, 3> &t2s_2,
 
    5               const Tensor2_symmetric<double, 3> &t2s_3,
 
    6               Dg<double, 3, 3> &t3dg_1, 
const Dg<double, 3, 3> &t3dg_2,
 
    7               const Dg<double, 3, 3> &t3dg_3);
 
void test_T3dg(Tensor1< double, 3 > &t1_1, const Tensor1< double, 3 > &t1_2, Tensor2< double, 3, 3 > &t2_1, const Tensor2< double, 3, 3 > &t2_2, Tensor2_symmetric< double, 3 > &t2s_1, const Tensor2_symmetric< double, 3 > &t2s_2, const Tensor2_symmetric< double, 3 > &t2s_3, Dg< double, 3, 3 > &t3dg_1, const Dg< double, 3, 3 > &t3dg_2, const Dg< double, 3, 3 > &t3dg_3)