sub ReportErstellen 
{
  my $file = shift;
  my $title = shift;
  my $osm_data = shift;
  my %poi_id_ref = %{shift};
  my %poi_name_ref = %{shift};
  my %conf_ref = %{shift};

#oder:
  my $poi_id_ref = shift;
  $poi_id_ref->{key} = value; # hier dereferenziert der -> Operator