Main features:

• Isoparametric hexahedra,
• Isotropic and anisotropic mesh refinements,
• Interface with a Geometric Modeling Package (both for an initial mesh generation  and  mesh refinements),
• New data structure in Fortran 90,
• New implementation of constrained approximation (information about a constrained element reconstructed from  information stored for its father),
• Separation of logical operations in the mesh refinement routines into two levels:
  • operations for nodes (an abstraction for element vertices, edges, and interiors) -  problem independent.
  • operation for nodal degrees of freedom - problem dependent

3Dhp90 manual

Source code  (Follow the instructions given below to decode the source code)

To decode the file:
 * use gunzip to decompress 2Dhp90.tar.gz into 2Dhp90.tar
 * use "tar xvf 2Dhp90.tar" to create the directory with the code