diff --git a/include/MatrixMath.h b/include/MatrixMath.h
index 6a42d970..1799fd07 100644
--- a/include/MatrixMath.h
+++ b/include/MatrixMath.h
@@ -309,6 +309,17 @@ template<class T> std::string vec_to_string(const std::vector<T> &a, const char
 template<class T> std::string vec_to_string(const std::vector<T> &a) {
     return vec_to_string(std::vector<double>(a.begin(), a.end()), stdFmt);
 };
+///Templates for turning vectors (1D-matrices) into strings
+inline std::string stringvec_to_string(const std::vector<std::string> &a) {
+    if (a.size()<1) return std::string("");
+    std::stringstream out;
+    out << "[ " << format("%s", a[0].c_str());
+    for (size_t j = 1; j < a.size(); j++) {
+        out << ", " << format("%s", a[j].c_str());
+    }
+    out << " ]";
+    return out.str();
+};
 
 /// Templates for turning numbers (0D-matrices) into strings
 template<class T> std::string vec_to_string(const T &a, const char *fmt) {
diff --git a/src/AbstractState.cpp b/src/AbstractState.cpp
index 3580e6fa..e2d88cb4 100644
--- a/src/AbstractState.cpp
+++ b/src/AbstractState.cpp
@@ -25,6 +25,9 @@ namespace CoolProp {
 
 AbstractState * AbstractState::factory(const std::string &backend, const std::vector<std::string> &fluid_names)
 {
+    if (get_debug_level() > 0){
+        std::cout << "AbstractState::factory(" << backend << "," << stringvec_to_string(fluid_names) << ")" << std::endl;
+    }
     static const std::string HEOS_string = "HEOS";
     if (!backend.compare(HEOS_string))
     {