Thanks vroom, When I plug this into a loop I am getting these results . I am confused. They are all Mondays but just not always the first Monday. 
foreach my $item (1..12) {
my $year = 2003;
my $month = $item;
my $day = 12;
my ($week,undef)=Week_of_Year($year,$month,$day);
my (undef, $tmpmonth, $firstmonday)=Monday_of_Week($week,$year);
if ($tmpmonth != $month)
{
(undef, undef, $firstmonday)=Monday_of_Week(++$week,$year);
}

[download]
First monday of 1/2003 is 6
First monday of 2/2003 is 10
First monday of 3/2003 is 10
First monday of 4/2003 is 7
First monday of 5/2003 is 12
First monday of 6/2003 is 9
First monday of 7/2003 is 7
First monday of 8/2003 is 11
First monday of 9/2003 is 8
First monday of 10/2003 is 6
First monday of 11/2003 is 10
First monday of 12/2003 is 8

In reply to Re: Re: getting the First day of the month by Anonymous Monk
in thread getting the First day of the month by Anonymous Monk

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