Both Nicolay and Frederic have given you a good starting point. Agree with Frederic that you will need to provide or better define the issue you are going to expand on. There are various views on Social Entrepreneurship, there are also a number regarding sustainability e.g. financial, organizational, rural or environmental.
I would look up Erik G. Hansen, Chux Inu and Heather Douglas on this site and take a look at their work in this area. Externally, Moizer and Tracey 2010 work could be of help as well, Saunah Zainon et al 2014, who look at sustainability from a Malaysian perspective.
I agree with Frederic that you will need to provide a better definition of the issue you are going to work on. There are many definitions of social entrepreneurship. Also plenty of articles are available on the subject. Kindly go through the data bases like EBSCO, Proquest, T Stor etc.
Social Entrepreneurship, there are also a number regarding sustainability e.g. financial, organizational, rural or environmental.
I agree that all the aforementioned authors are highly relevant. Perhaps the following article would be helpful as well:
Rey-Martí, A., et al., A bibliometric analysis of social entrepreneurship, Journal of Business Research (2015), http://dx.doi.org/10.1016/j.jbusres.2015.10.033
Thank you Olivera, Arun, Oguzhan, James, Robert, Frederick, and Nikolay for you very helpful responses and resources. Some I knew of (Borenstein, Yanus) but others were very new. Thank you too for asking me to go deeper into my definition and conceptualization of SE. This is great! The book is due out iAug. and I will be working on it in earnest the end of the semester (May). Thanks again!