*Heading
 S4R Elements
*Node
      1,          -5.,          2.5,           0.
      2,          -5.,           0.,           0.
      3,          -5.,         -2.5,           0.
      4,         -2.5,          2.5,           0.
      5,         -2.5,           0.,           0.
      6,         -2.5,         -2.5,           0.
      7,           0.,          2.5,           0.
      8,           0.,           0.,           0.
      9,           0.,         -2.5,           0.
     10,          2.5,          2.5,           0.
     11,          2.5,           0.,           0.
     12,          2.5,         -2.5,           0.
     13,           5.,          2.5,           0.
     14,           5.,           0.,           0.
     15,           5.,         -2.5,           0.
*Element, type=S4R
1,  1,  2,  5,  4
2,  2,  3,  6,  5
3,  4,  5,  8,  7
4,  5,  6,  9,  8
5,  7,  8, 11, 10
6,  8,  9, 12, 11
7, 10, 11, 14, 13
8, 11, 12, 15, 14
*Elset, elset=I1, generate
 1,  8,  1
*Shell Section, elset=I1, material=Elas
0.5, 5
*Material, name=Elas
*Density
40
*Elastic
 1e+08,0.
** ----------------------------------------------------------------
*step
*frequency,eigen=lanc
20,
*boundary
1,1,6
3,1,6
13,1,6
15,1,6
*end step
*STEP
*substructure generate, type=z1, overwrite, 
recovery matrix=yes, mass matrix=yes,
libr=lib_smdef_shell3D
*RETAINED NODAL DOFS,sorted=no
1,1,6
3,1,6
13,1,6
15,1,6
*SELECT EIGENMODES,generate
1,20,1
*substructure matrix output, stiffness=yes, 
mass=yes, recovery=yes, file=lib_smdef_shell3D
*END STEP