diff --git a/README.md b/README.md
index c359c33..10597c0 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
 TOMS748
 =======
 Implementation in C++ and python of the very efficient TOMS748 root-finding algorithm. (Yes, there is already a version in boost).
+
+Source : https://na.math.kit.edu/alefeld/download/1995_Algorithm_748_Enclosing_Zeros_of_Continuous_Functions.pdf
diff --git a/cpp/TOMS748.hpp b/cpp/TOMS748.hpp
index 9e5fdce..4c1c75f 100644
--- a/cpp/TOMS748.hpp
+++ b/cpp/TOMS748.hpp
@@ -134,6 +134,8 @@ namespace TOMS748
     /// Algorithm 4.1 from TOMS748 of robust root-solving.
     /// Use this version if f(a) and f(b) have already been computed.
     /// Returns x, f(x), and a boolean indicating if the function converged or not (true if converged).
+    ///
+    /// Source : https://na.math.kit.edu/alefeld/download/1995_Algorithm_748_Enclosing_Zeros_of_Continuous_Functions.pdf
     template<typename Func, typename T>
     std::tuple<T,T,bool> TOMS748_solve1(Func f, T a, T b, T fa, T fb, T tol, unsigned int Nmax = 1000)
     {