diff --git a/performance.c b/performance.c
index 0f46213..f0ab098 100644
--- a/performance.c
+++ b/performance.c
@@ -1,7 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
-#include "src/gll.h"
+#include "./src/gll.h"
 
 static float start();
 static void stop(float);
diff --git a/src/gll.c b/src/gll.c
index 5bc024a..0f417cc 100644
--- a/src/gll.c
+++ b/src/gll.c
@@ -5,7 +5,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include "gll.h"
+#include "./gll.h"
 
 #define C_OK 0
 #define C_NOK -1
diff --git a/src/gll.h b/src/gll.h
index 9eb97d7..bc182db 100644
--- a/src/gll.h
+++ b/src/gll.h
@@ -6,6 +6,10 @@
 /*
  * Node Type: gll_node_t struct
  */
+
+#ifndef GLL_H
+#define GLL_H
+
 typedef struct node_t {
   void *data;
   struct node_t *prev;
@@ -49,3 +53,4 @@ void gll_eachReverse(gll_t *, void (*f)(void *));
 void gll_clear(gll_t *);
 void gll_destroy(gll_t *);
 
+#endif //GLL_H
\ No newline at end of file
diff --git a/tests.c b/tests.c
index 5ddfcf5..66a8bcf 100644
--- a/tests.c
+++ b/tests.c
@@ -3,7 +3,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <string.h>
-#include "src/gll.h"
+#include "./src/gll.h"
 
 #define MAX_STR 32
 #define C_OK    0