Study Of Sources Of Methane Emission, Development Of Recommendations For Making An Addition To The "Project Of Ventilation Of The Bilytska Mine Due To Natural Draft With Turned Off Vhp" In The Part Of The Length Of Ventilated Mine Workings And To Develop Recommendations For The Ventilation Of The "Bilytska" Mine For The Period Of Repayment Of The Bypass Work Of The Rock Complex Of Mountains 250 M" (EXPIRED)