Thank you for your opinions.
My research interests are in corporate finance. At present, I collaborate with my university (it is a not well known one internationally, but it is the first and the most selective - that's to say GPAs are generally low - technical school in my country). I'm researching (a bit, of course, my job is very time consuming) about Neural Networks applications in banking and finance, but I would like to research about corporate finance (enterprise valuation, M&As, private equity, and so on).
I have three LORs, from a full professor of banking and finance, from a post-doctoral research fellow in banking and finance, and a non-academic one from one former reseach fellow (he holds a PHd) - in another discipline - who decided to run his own business (I collaborated with him on a couple on projects). Of course, since my university is not well known, my professors are not well known too.
In september I'm going to take the TOEFL test too.
I decided to apply to the following schools (Ultra Elite + "Safety schools"): MIT, Wharton, Stanford, Berkeley, New York Stern, Kellogg (Northwestern), Harvard, Michigan (Ross), Simon (Rochester), Warrington, Purdue, Krannert (Indiana), Cornell (Johnson).
Cheers