diff --git a/server/gameserver/car.cc b/server/gameserver/car.cc
index 9c2ee75f..3f8cc812 100644
--- a/server/gameserver/car.cc
+++ b/server/gameserver/car.cc
@@ -339,7 +339,7 @@ void Car::OnExplosionHit(Explosion* e)
 }
 
 void Car::DecHP(float dec_hp, int killer_id, const std::string& killer_name, int weapon_id,
-                int real_killer_id, const std::string& real_killer_name,
+                int real_killer_id, const std::string real_killer_name,
                 float& real_dmg_out)
 {
     real_dmg_out = 0.0f;
diff --git a/server/gameserver/car.h b/server/gameserver/car.h
index e192302a..a9425628 100644
--- a/server/gameserver/car.h
+++ b/server/gameserver/car.h
@@ -37,7 +37,7 @@ class Car : public Creature
     virtual float GetSpeed() override;
     virtual void DecHP(float dec_hp,
                        int killer_id, const std::string& killer_name, int weapon_id,
-                       int real_killer_id, const std::string& real_killer_name,
+                       int real_killer_id, const std::string real_killer_name,
                        float& real_dmg_out) override;
     virtual void SendDebugMsg(const std::string& debug_msg) override;
     virtual void SetAttackDir(const glm::vec3& attack_dir) override;
diff --git a/server/gameserver/creature.h b/server/gameserver/creature.h
index 183eba57..cdad1760 100644
--- a/server/gameserver/creature.h
+++ b/server/gameserver/creature.h
@@ -221,7 +221,7 @@ class Creature : public MoveableEntity
     Car* AsCar() { return IsCar() ? (Car*)this : nullptr; };
     virtual void DecHP(float dec_hp, int killer_id,
                        const std::string& killer_name, int weapon_id,
-                       int real_killer_id, const std::string& real_killer_name,
+                       int real_killer_id, const std::string real_killer_name,
                        float& real_dmg_out) {};
     void AddHp(float hp);
     void SetHP(float hp);
diff --git a/server/gameserver/hero.cc b/server/gameserver/hero.cc
index b9fdf22c..1a9b0305 100644
--- a/server/gameserver/hero.cc
+++ b/server/gameserver/hero.cc
@@ -168,7 +168,7 @@ void Hero::DetachFromMaster()
 }
 
 void Hero::DecHP(float dec_hp, int killer_id, const std::string& killer_name, int weapon_id,
-                 int real_killer_id, const std::string& real_killer_name,
+                 int real_killer_id, const std::string real_killer_name,
                  float& real_dmg_out)
 {
     real_dmg_out = 0.0f;
diff --git a/server/gameserver/hero.h b/server/gameserver/hero.h
index 3d081d64..7674762c 100644
--- a/server/gameserver/hero.h
+++ b/server/gameserver/hero.h
@@ -26,7 +26,7 @@ public:
     virtual void Update(int delta_time) override;
     virtual void DecHP(float dec_hp,
                        int killer_id, const std::string& killer_name, int weapon_id,
-                       int real_killer_id, const std::string& real_killer_name,
+                       int real_killer_id, const std::string real_killer_name,
                        float& real_dmg_out) override;
     virtual std::string GetName() override;
     virtual void DropItems(Obstacle* obstacle) override;
diff --git a/server/gameserver/human.cc b/server/gameserver/human.cc
index cc7fe1c1..77969a02 100644
--- a/server/gameserver/human.cc
+++ b/server/gameserver/human.cc
@@ -644,7 +644,7 @@ void Human::BeKill(int killer_id, const std::string& killer_name, int weapon_id,
 }
 
 void Human::DecHP(float dec_hp, int killer_id, const std::string& killer_name, int weapon_id,
-                  int real_killer_id, const std::string& real_killer_name,
+                  int real_killer_id, const std::string real_killer_name,
                   float& real_dmg_out)
 {
     real_dmg_out = 0.0f;
diff --git a/server/gameserver/human.h b/server/gameserver/human.h
index 14e46a36..1ed95565 100644
--- a/server/gameserver/human.h
+++ b/server/gameserver/human.h
@@ -303,7 +303,7 @@ class Human : public Creature
                 int real_killer_id, const std::string& real_killer_name);
     virtual void DecHP(float dec_hp,
                        int killer_id, const std::string& killer_name, int weapon_id,
-                       int real_killer_id, const std::string& real_killer_name,
+                       int real_killer_id, const std::string real_killer_name,
                        float& real_dmg_out) override;
     virtual void AddToNewObjects(Entity* entity) override;
     virtual void AddToPartObjects(Entity* entity) override;