my $abstract=shift @{$HASH->{$Title}->{???}}#here I need to access each single title in order to get the first element of each (anonymous) hash
print "<abstract>"."$abstract"."</abstract>\n";

#here I should print all the element between the first  and the last one of the array in each single hash

my $procedure=pop @{$HASH->{$Title}}#same as before
print "<procedure>"."$procedure"."</procedure>\n";