diff --git a/krylov/mld_krylov_mod.f90 b/krylov/mld_krylov_mod.f90
index 03acc3ff..40e8256e 100644
--- a/krylov/mld_krylov_mod.f90
+++ b/krylov/mld_krylov_mod.f90
@@ -201,6 +201,52 @@ Module mld_krylov_mod
 contains
 
 
+  !
+  ! File: mld_krylov_mod.f90
+  !
+  ! Subroutine: mld_dkrylov
+  ! 
+  !    Front-end for the Krylov subspace iterations, real version
+  !    
+  ! Arguments:
+  !
+  !    methd  -  character                    The specific method; can take the values:
+  !                                           CG
+  !                                           CGS
+  !                                           BICG
+  !                                           BICGSTAB
+  !                                           BICGSTABL
+  !                                           RGMRES
+  !                                           
+  !    a      -  type(<psb_dspmat_type>)      Input: sparse matrix containing A.
+  !    prec   -  type(<mld_dprec_type>)       Input: preconditioner
+  !    b      -  real,dimension(:)            Input: vector containing the
+  !                                           right hand side B
+  !    x      -  real,dimension(:)            Input/Output: vector containing the
+  !                                           initial guess and final solution X.
+  !    eps    -  real                         Input: Stopping tolerance; the iteration is
+  !                                           stopped when the error estimate
+  !                                           |err| <= eps
+  !    desc_a -  type(<psb_desc_type>).       Input: The communication descriptor.
+  !    info   -  integer.                     Output: Return code
+  !
+  !    itmax  -  integer(optional)            Input: maximum number of iterations to be
+  !                                           performed.
+  !    iter   -  integer(optional)            Output: how many iterations have been
+  !                                           performed.
+  !    err    -  real   (optional)            Output: error estimate on exit
+  !    itrace -  integer(optional)            Input: print an informational message
+  !                                           with the error estimate every itrace
+  !                                           iterations
+  !    irst   -  integer(optional)            Input: restart parameter for RGMRES and 
+  !                                           BICGSTAB(L) methods
+  !    istop  -  integer(optional)            Input: stopping criterion, or how
+  !                                           to estimate the error. 
+  !                                           1: err =  |r|/|b|
+  !                                           2: err =  |r|/(|a||x|+|b|)
+  !                                           where r is the (preconditioned, recursive
+  !                                           estimate of) residual 
+  ! 
   Subroutine mld_dkrylov(method,a,prec,b,x,eps,desc_a,info,&
        &itmax,iter,err,itrace,irst,istop)
 
@@ -274,6 +320,50 @@ contains
   end subroutine mld_dkrylov
 
 
+
+  !
+  ! File: mld_krylov_mod.f90
+  !
+  ! Subroutine: mld_zkrylov
+  ! 
+  !    Front-end for the Krylov subspace iterations, complexversion
+  !    
+  ! Arguments:
+  !
+  !    methd  -  character                    The specific method; can take the values:
+  !                                           CGS
+  !                                           BICGSTAB
+  !                                           RGMRES
+  !                                           
+  !    a      -  type(<psb_zspmat_type>)      Input: sparse matrix containing A.
+  !    prec   -  type(<mld_zprec_type>)       Input: preconditioner
+  !    b      -  complex,dimension(:)         Input: vector containing the
+  !                                           right hand side B
+  !    x      -  complex,dimension(:)         Input/Output: vector containing the
+  !                                           initial guess and final solution X.
+  !    eps    -  real                         Input: Stopping tolerance; the iteration is
+  !                                           stopped when the error estimate
+  !                                           |err| <= eps
+  !    desc_a -  type(<psb_desc_type>).       Input: The communication descriptor.
+  !    info   -  integer.                     Output: Return code
+  !
+  !    itmax  -  integer(optional)            Input: maximum number of iterations to be
+  !                                           performed.
+  !    iter   -  integer(optional)            Output: how many iterations have been
+  !                                           performed.
+  !    err    -  real   (optional)            Output: error estimate on exit
+  !    itrace -  integer(optional)            Input: print an informational message
+  !                                           with the error estimate every itrace
+  !                                           iterations
+  !    irst   -  integer(optional)            Input: restart parameter for RGMRES and 
+  !                                           BICGSTAB(L) methods
+  !    istop  -  integer(optional)            Input: stopping criterion, or how
+  !                                           to estimate the error. 
+  !                                           1: err =  |r|/|b|
+  !                                           2: err =  |r|/(|a||x|+|b|)
+  !                                           where r is the (preconditioned, recursive
+  !                                           estimate of) residual 
+  ! 
   Subroutine mld_zkrylov(method,a,prec,b,x,eps,desc_a,info,&
        &itmax,iter,err,itrace,irst,istop)
     use psb_base_mod