FMZM90 (related to FMLIB),
developed by David Smith of Loyola Marymount University,
is a Fortran-90 module that defines three derived types:
multiple-precision real, multiple-precision integer, and multiple-precision complex.
Interfaces are provided so that a program can declare variables to be multiple-precision types
and then write the code for multiple-precision operations using normal Fortran syntax.