LNK 2001 with static variables C++

I'm trying to make my variables in class static. I wrote this code and got several LNK 2001 errors for each variable in class. I have no idea what can promote to this behaviour. Please, help me

Code:

GameObject.h

#pragma once

using namespace std;
using namespace glm;

class GameObject
{
private:

    static int id;
    static string name;
    static string sprite;
    static vec2 position;
    static vec2 scale;

public:

    GameObject(string _name, string _spr, vec2 _pos, vec2 _scale);

    void move(vec2 dir);
};

GameObject.cpp

GameObject::GameObject(string _name, string _spr, vec2 _pos, vec2 _scale)
{
    name = _name;
    sprite = _spr;
    position = _pos;
    scale = _scale;
}

void GameObject::move(vec2 dir)
{
    position += dir;
}