diff --git a/src/ainotes.cls b/src/ainotes.cls
index 794e6ed..05ae063 100644
--- a/src/ainotes.cls
+++ b/src/ainotes.cls
@@ -103,4 +103,11 @@
 }
 
 
+\newcommand{\gitFAIKROne}[0]{   https://github.com/NotXia/unibo-ai-notes/tree/pdfs/fundamentals-of-ai-and-kr/module1            }
+\newcommand{\gitFAIKRTwo}[0]{   https://github.com/NotXia/unibo-ai-notes/tree/pdfs/fundamentals-of-ai-and-kr/module2            }
+\newcommand{\gitFAIKRThree}[0]{ https://github.com/NotXia/unibo-ai-notes/tree/pdfs/fundamentals-of-ai-and-kr/module3            }
+\newcommand{\gitLAAITwo}[0]{    https://github.com/NotXia/unibo-ai-notes/tree/pdfs/languages-and-algorithms-for-ai/module2      }
+\newcommand{\gitMLDM}[0]{       https://github.com/NotXia/unibo-ai-notes/tree/pdfs/machine-learning-and-data-mining             }
+\newcommand{\gitSMM}[0]{        https://github.com/NotXia/unibo-ai-notes/tree/pdfs/statistical-and-mathematical-methods-for-ai  }
+
 \newcommand{\eoc}[0]{\begin{flushright}\texttt{\raggedleft\small <end of course>}\end{flushright}}
\ No newline at end of file
diff --git a/src/fundamentals-of-ai-and-kr/module2/sections/_logic.tex b/src/fundamentals-of-ai-and-kr/module2/sections/_logic.tex
index dd9114a..8b99a47 100644
--- a/src/fundamentals-of-ai-and-kr/module2/sections/_logic.tex
+++ b/src/fundamentals-of-ai-and-kr/module2/sections/_logic.tex
@@ -1,6 +1,6 @@
 \newpage
-\lohead{\color{gray} Chapter taken from \href{https://github.com/NotXia/unibo-ai-notes/tree/pdfs/languages-and-algorithms-for-ai/module2}{\texttt{\color{gray}Languages and Algorithms for AI (module 2)}}}
-\lehead{\color{gray} Chapter taken from \href{https://github.com/NotXia/unibo-ai-notes/tree/pdfs/languages-and-algorithms-for-ai/module2}{\texttt{\color{gray}Languages and Algorithms for AI (module 2)}}}
+\lohead{\color{gray} Chapter taken from \href{\gitLAAITwo}{\texttt{\color{gray}Languages and Algorithms for AI (module 2)}}}
+\lehead{\color{gray} Chapter taken from \href{\gitLAAITwo}{\texttt{\color{gray}Languages and Algorithms for AI (module 2)}}}
 
 \graphicspath{{../../languages-and-algorithms-for-ai/module2/}}
 \input{../../languages-and-algorithms-for-ai/module2/sections/_propositional_logic.tex}
diff --git a/src/fundamentals-of-ai-and-kr/module2/sections/_prolog.tex b/src/fundamentals-of-ai-and-kr/module2/sections/_prolog.tex
index f69947e..a2a0859 100644
--- a/src/fundamentals-of-ai-and-kr/module2/sections/_prolog.tex
+++ b/src/fundamentals-of-ai-and-kr/module2/sections/_prolog.tex
@@ -2,7 +2,7 @@
 
 
 It may be useful to first have a look at the "Logic programming" section of 
-\href{https://github.com/NotXia/unibo-ai-notes/tree/pdfs/languages-and-algorithms-for-ai/module2}{\texttt{Languages and Algorithms for AI (module 2)}}.
+\href{\gitLAAITwo}{\texttt{Languages and Algorithms for AI (module 2)}}.
 
 
 \section{Syntax}
diff --git a/src/languages-and-algorithms-for-ai/module2/sections/_prolog.tex b/src/languages-and-algorithms-for-ai/module2/sections/_prolog.tex
index 32ee37a..9dc7359 100644
--- a/src/languages-and-algorithms-for-ai/module2/sections/_prolog.tex
+++ b/src/languages-and-algorithms-for-ai/module2/sections/_prolog.tex
@@ -1,6 +1,6 @@
 \newpage
-\lohead{\color{gray} Chapter taken from \href{https://github.com/NotXia/unibo-ai-notes/tree/pdfs/fundamentals-of-ai-and-kr/module2}{\texttt{\color{gray}Fundamentals of AI and KR (module 2)}}}
-\lehead{\color{gray} Chapter taken from \href{https://github.com/NotXia/unibo-ai-notes/tree/pdfs/fundamentals-of-ai-and-kr/module2}{\texttt{\color{gray}Fundamentals of AI and KR (module 2)}}}
+\lohead{\color{gray} Chapter taken from \href{\gitFAIKRTwo}{\texttt{\color{gray}Fundamentals of AI and KR (module 2)}}}
+\lehead{\color{gray} Chapter taken from \href{\gitFAIKRTwo}{\texttt{\color{gray}Fundamentals of AI and KR (module 2)}}}
 
 \graphicspath{{../../fundamentals-of-ai-and-kr/module2/}}
 \input{../../fundamentals-of-ai-and-kr/module2/sections/_prolog.tex}