diff --git a/LU_decomposition/LU_Decomposition.ipynb b/LU_decomposition/LU_Decomposition.ipynb
index d5b251c..e370abe 100644
--- a/LU_decomposition/LU_Decomposition.ipynb
+++ b/LU_decomposition/LU_Decomposition.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2015 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# LU Decomposition"
    ]
   },
diff --git a/binomial_option_pricing/binomial_option_pricing.ipynb b/binomial_option_pricing/binomial_option_pricing.ipynb
index 29ac67f..9960e8a 100644
--- a/binomial_option_pricing/binomial_option_pricing.ipynb
+++ b/binomial_option_pricing/binomial_option_pricing.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2012 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# Binomial Option Pricing"
    ]
   },
diff --git a/black_litterman/black_litterman.ipynb b/black_litterman/black_litterman.ipynb
index 8e8b320..8504ef9 100644
--- a/black_litterman/black_litterman.ipynb
+++ b/black_litterman/black_litterman.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2013 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# Portfolio Optimization and Black-Litterman"
    ]
   },
diff --git a/heath_jarrow_morton/hjm.ipynb b/heath_jarrow_morton/hjm.ipynb
index fd19633..962810e 100644
--- a/heath_jarrow_morton/hjm.ipynb
+++ b/heath_jarrow_morton/hjm.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2015 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# Heath Jarrow Morton Model (HJM)"
    ]
   },
diff --git a/principal_component_analysis/PCA.ipynb b/principal_component_analysis/PCA.ipynb
index f69b05f..3d33209 100644
--- a/principal_component_analysis/PCA.ipynb
+++ b/principal_component_analysis/PCA.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2015 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# Principal Component Analysis (PCA)"
    ]
   },
diff --git a/time_value_of_money/tvm.ipynb b/time_value_of_money/tvm.ipynb
index 9ed25fa..67cf04a 100644
--- a/time_value_of_money/tvm.ipynb
+++ b/time_value_of_money/tvm.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2012 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# Time Value of Money"
    ]
   },
diff --git a/yield_curve_bootstrapping/bootstrapping.ipynb b/yield_curve_bootstrapping/bootstrapping.ipynb
index 7f61c87..1967bf2 100644
--- a/yield_curve_bootstrapping/bootstrapping.ipynb
+++ b/yield_curve_bootstrapping/bootstrapping.ipynb
@@ -6,7 +6,7 @@
    "source": [
     "Copyright © 2012 Ondrej Martinsky, All rights reserved\n",
     "\n",
-    "[www.quantandfinancial.com](www.quantandfinancial.com)\n",
+    "[www.quantandfinancial.com](http://www.quantandfinancial.com)\n",
     "# Treasury Yield Curve Bootstrapping"
    ]
   },