Why companies have to report about their social and environmental activities (different theories).

Description

The main idea of the research is about sustainability disclosures and reports of oil and gas companies in Abu Dhabi regarding the environmental and social aspects.
Organize the existed literature review and divide it into two parts 
(a)    Environmental
(b)    Social 
The literature review should talk about 
Why companies have to report about their social and environmental activities (different theories).
What are the international standards of reporting and disclosing social and environmental sustainability activities? (different theories)
Choose 3 largest governmental companies and 3 largest private companies, and check if they are reporting and disclosing their environmental and social sustainability activities and on which basis.