Developers:
    Pavel Zacherle (zapa@ipe.muni.cz)

Third-party code:
Subroutine RDCALCDP (https://www.seismotoolbox.ca/EXSIM12/EXSIM12.for)
    J.M. Roesset, 1971
    Stavros A. Anagnostopoulos, Oct. 1986
    David M. Boore, 1995, 1996
    


