diff --git a/SharedData/SharedData.c b/SharedData/SharedData.c
index 5a2df17..2e98e86 100644
--- a/SharedData/SharedData.c
+++ b/SharedData/SharedData.c
@@ -73,6 +73,10 @@ void wait_all_threads_SharedData(THIS(SharedData)){
 		pthread_join(this->threads[i], NULL);
 }
 
+int use_call_box_SharedData(THIS(SharedData), char * resident_name){
+	return this->main_building->use_call_box(this->main_building, resident_name);
+}
+
 void _free__SharedData(THIS(SharedData)){
 	int i;
 	if (this->threads != NULL){
@@ -102,6 +106,7 @@ SharedData *_get_instance_SharedData(){
 				 wait_all_threads,
 				 set_main_building,
 				 get_main_building,
+				 use_call_box,
 				 call_elevator
 		);
 	}
diff --git a/SharedData/SharedData.h b/SharedData/SharedData.h
index 953721c..451b4c4 100644
--- a/SharedData/SharedData.h
+++ b/SharedData/SharedData.h
@@ -9,15 +9,9 @@
 #include "../Objects.h"
 #include "../Building/Building.h"
 
-#define MUTEX_NB 3
-
-enum {mutex_1, mutex_2, mutex_3};
-
 typedef struct o_SharedData {
 	PRIVATE int threads_nb;
 	PRIVATE pthread_t *threads;
-	PRIVATE pthread_mutex_t mutex_array[MUTEX_NB];
-
 	PRIVATE Building * main_building;
 
 	PRIVATE void (*start_thread)(_THIS(SharedData), void * (*thread)(void *), void * data, int thread_number);
@@ -28,6 +22,7 @@ typedef struct o_SharedData {
 	PUBLIC Building * (*get_main_building)(_THIS(SharedData));
 	PUBLIC void (*wait_threads)(_THIS(SharedData));
 	PUBLIC int (*call_elevator)(_THIS(SharedData), int starting_floor, int destination_floor);
+	PUBLIC int (*use_call_box)(_THIS(SharedData), char * resident_name);
 
 	DESTRUCTOR(SharedData);
 } SharedData;
diff --git a/Visitor/Visitor.c b/Visitor/Visitor.c
index 16eae0b..c77c75a 100644
--- a/Visitor/Visitor.c
+++ b/Visitor/Visitor.c
@@ -13,7 +13,7 @@ void * runnable_Visitor(void * void_this){
 	Visitor *this = (Visitor*) void_this;
 	SharedData * data = GET_INSTANCE(SharedData);
 	printf("Bonjour, je suis %s et je souhaite rendre visite a %s\n", this->name, this->contact_name);
-	printf("Bip, %s appel a l'interphone\n%s habite a l'etage %d\n", this->name, this->contact_name, data->main_building->use_call_box(data->main_building, this->contact_name));
+	printf("Bip, %s appel a l'interphone\n%s habite a l'etage %d\n", this->name, this->contact_name, data->use_call_box(data, this->contact_name));
 	return NULL;
 }