Tinjauan yuridis atas rencana penggabungan perusahaan merger dalam industri migas berdasarkan aspek hukum persaingan usaha : studi kasus rencana merger PT. Perusahaan Gas Negara dan PT. Pertamina Gas = Legal review of merger process in oil gas industries based on competition law perspective : case studies of merger plan PT. Perusahaan Gas Negara and PT. Pertamina Gas