You can read about Serbian modern history in books written by Dimitrije Đorđević, Trajan Stojanović (they worked in the USA) and Dragoljub Živojinović (PhD degree at the University of Pennsylvania). They translated some of their books in English. You can find a book Disraeli and the Eastern Question by Miloš Ković. Miloš Ković is a professor at the University of Belgrade. I know him..
I did not know.