salam doct .I hope t be well.so i suggest use descriptif théorique in this proget

I think that Issue area approach will be helpful for your research  

have a look AT 

James N. Rosenau, "Pre-theories and Theories of Foreign Policy," in

‘Issue Area and Foreign Policy Analysis’, International Organization,

vol .34 (1980), 405–427.

Thomas L . Brewer, ‘AN ISSUE-AREA APPROACH TO THE ANALYSIS OF MNE-GOVERNMENT RELATIONS’, Journal of International Business Studies, 23 (1992),

Anwer Qayum, ‘THE CONCEPT OF ISSUE-AREA IN FOREIGN POLICY ANALYSIS’, Pakistan Institute of International Affairs, 30 (1977), 43–53 (pp. 43–53).

WITH MY REGARDS

Bachir Chaib,

 I haven't done any work on the ethnic conflict and regional integration. But have done  some work on ethnic conflict and post war rebuilding. See below article if it is any help for your work.

Article The Post- conflict Rebuilding Process of Sri Lanka: A Conten...

Greetings, regarding ethnic conflict theories, you may also refer to:

Theories of Nationalism by Umut Ozkirimli. Palgrave Macmillan, 2010.  

Ethnic Conflict: A Systematic Approach to Cases of Conflict by Neal G. Jesse and Kristen P. Willilams. Washington: CQ Press, 2011.

Modern Hatreds: The Symbolic Politics of Ethnic War by Stuart J. Kaufman Ithaca, NY: Cornell University Press, 2001.

Case studies inclusive with survey data, if available.

Theoretical analysis entwined with specific case study analysis.