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diff --git a/challenge-167/adam-russell/blog.txt b/challenge-167/adam-russell/blog.txt
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+++ b/challenge-167/adam-russell/blog.txt
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+http://www.rabbitfarm.com/cgi-bin/blosxom/perl/2022/06/05
diff --git a/challenge-167/adam-russell/perl/ch-1.pl b/challenge-167/adam-russell/perl/ch-1.pl
new file mode 100644
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+++ b/challenge-167/adam-russell/perl/ch-1.pl
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+use strict;
+use warnings;
+##
+# Write a script to find out first 10 circular primes having at least 3 digits (base 10).
+##
+use boolean;
+use Math::Primality qw/is_prime/;
+
+sub is_circular_prime{
+    my($x) = @_;
+    my @digits = split(//, $x);
+    for my $i (0 .. @digits - 1){
+        @digits = (@digits[1 .. @digits - 1], $digits[0]);
+        my $candidate = join("", @digits) + 0;
+        return false if !is_prime($candidate);
+    }
+    return true;
+}
+
+sub first_n_circular_primes{
+    my($n) = @_;
+    my $i = 100;
+    my %circular;
+    my @circular_primes;
+    {
+        if(is_circular_prime($i) && !$circular{join("", sort {$a <=> $b} split(//, $i))}){
+            push @circular_primes, $i; 
+            $circular{join("", sort {$a <=> $b} split(//, $i))} = -1;
+        }
+        $i++;
+        redo if @circular_primes < $n;
+    }
+    return @circular_primes;
+}
+
+sub first_10_circular_primes{
+    return first_n_circular_primes(10);
+}
+
+MAIN:{
+    print join(", ", first_10_circular_primes()) . "\n";
+}
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diff --git a/challenge-167/adam-russell/perl/ch-2.pl b/challenge-167/adam-russell/perl/ch-2.pl
new file mode 100644
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+++ b/challenge-167/adam-russell/perl/ch-2.pl
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+use strict;
+use warnings;
+##
+# Implement a subroutine gamma() using the Lanczos approximation method.
+##
+use POSIX;
+use Math::Complex;
+
+use constant EPSILON => 1e-07;
+
+sub lanczos{
+    my($z) = @_;
+    my @p = (676.5203681218851, -1259.1392167224028, 771.32342877765313, -176.61502916214059, 12.507343278686905, -0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7);
+    my $y;
+    $z = new Math::Complex($z);
+    if(Re($z) < 0.5){
+        $y = M_PI / (sin(M_PI * $z) * lanczos(1 - $z));
+    }
+    else{
+        $z -= 1;
+        my $x = 0.99999999999980993;
+        for my $i (0 .. @p - 1){
+            $x += ($p[$i] / ($z + $i + 1));
+        }
+        my $t = $z + @p - 0.5;
+        $y = sqrt(2 * M_PI) * $t ** ($z + 0.5) * exp(-1 * $t) * $x;
+    }
+    return Re($y) if abs(Im($y)) <= EPSILON;
+    return $y;
+}
+
+sub gamma{
+    return lanczos(@_);
+}
+
+MAIN:{
+    print gamma(3) . "\n";
+    print gamma(5) . "\n";
+    print gamma(7) . "\n";
+}
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