since they are obtained from experiments. In Unified we demonstrated that G=z( Eu. This expressions can be writen in the following matrix form: 吉一一旨00 000 000 2∈ 00 synn Invert and compare with A+2 000 入+2 000e A+2100 4002∈ e13 and conclude that E (1+u)(1-2)since they are obtained from experiments. In Unified we demonstrated that E G = 2(1+ν) . This expressions can be written in the following matrix form:      1 − ν − ν �11 E E E 0 0 0 σ11  �22   E − ν    1 0 0 0  E  σ22     1 0 0 0   �33  =  E 1  σ33  (22)    0 0   2�23   G  σ23  2�13  symm 1 0σ13 G 1 2�12 G σ12 Invert and compare with:      σ11 λ + 2µ µ µ 0 0 0 �11    λ + 2µ µ 0 0 0   σ22    �22     λ + 2µ 0 0 0   σ33  =   �33  (23)    µ 0 0   σ23    2�23  σ13  symm µ 2�13 σ12 µ 2�12 and conclude that: Eν λ = (1 + ν)(1 − 2ν) , µ = G (24) 4