Error in Class

I am getting 6 errors in my code. This is my first code on Operator Overloading in OOPS. I am getting undefined reference Complex :: Complex(double, double). Plz help me in fixing the error.
Here is my code :

//header file “Complex.h”
#ifndef COMPLEX_H_INCLUDED
#define COMPLEX_H_INCLUDED

#include

using namespace std;

class Complex
{
friend ostream &operator<<(ostream &, const Complex &);
friend istream &operator>>(istream &, Complex &);

public:

Complex(const Complex &);
~Complex();
Complex(double = 0.0, double = 0.0);
Complex operator+(const Complex &) const;
Complex operator-(const Complex &) const;
Complex operator*(const Complex &) const;

private:

double real;
double img;

};

#endif // COMPLEX_H_INCLUDED

//Header file “Complex1.h”
#ifndef COMPLEX1_H_INCLUDED
#define COMPLEX1_H_INCLUDED

#include
#include"Complex.h"
using namespace std;

Complex :: Complex(const Complex &c1)
: real(c1.real),
img(c1.img)
{

}
Complex :: ~Complex()
{

}

Complex Complex :: operator+(const Complex &right) const
{
Complex c3;

c3.real = real + right.real;
c3.img = img + right.img;
return c3;

}

Complex Complex :: operator-(const Complex &right) const
{
Complex c3;

c3.real = real - right.real;
c3.img = img - right.img;
return c3;

}

Complex Complex :: operator*(const Complex &right) const
{
Complex c3;

c3.real = real * right.real - img * right.img;
c3.img = real * right.img + img * right.real;
return c3;

}

istream &operator>>(istream &input, Complex &c1)
{
input>>c1.real;
input>>c1.img;

return input;

}

ostream &operator<<(ostream &output, const Complex &c2)
{
output<<setw(7)<<c2.real;
output<<setw(7)<<c2.img;

return output;

}

#endif // COMPLEX1_H_INCLUDED

#include"Complex1.h"

using namespace std;

int main()
{
Complex c1;
Complex c2;
Complex c3, c4, c5, c6;

cout<<"\nENTER c1 = "<<c1;
cout<<"\nENTER c2 = "<<c2;

c3 = c1 + c2;
c4 = c1 - c2;
c5 = c1 * c2;

cout<<"\nBEFORE INTIALISATION  c6: "<<c6;
cout<<"\nENTER c6 = ";
cin>>c6;

Complex c7(c6);

cout<<"\nc3 = "<<c3;
cout<<"\nc4 = "<<c4;
cout<<"\nc5 = "<<c5;
cout<<"\nc6 = "<<c6;
cout<<"\nc7 = "<<c7;

}