No Such User's Opinion 
Not sure if you're able to comprehend, but here are few facts to consider
Serbia was not a country during Selimović's life. Neither was Bosnia and Herzegovina. Yugoslavia was.
He was a partisan and a communist, and has fought for Yugoslav union in WW2 and thereafter
Selimović's declaration letter came in 1976, when he was 66, and it came as a result of conflicts and harrasment he had in Sarajevo
Serbian language is just a standardized variety of Serbo-Croatian, which is a linguistic unit. 
Statements on trial of Slobodan Milošević are not a relevant, reliable source for wikipedia. Biographies by relevant, nuanced biographers, such as Hayden  or Crnković  are.
Do you really think you're the first editor who came here to demand that we coy to requests for his uniquely Serbian / Bosniak nationality (cross the unnecessary) spoken in angry rants? The archives are full just of that nationalist crap. More sane and neutral editors, where I unhumbly count myself, reached a tacit agreement to go for outside sources, downplay his ethnicity crap, and tell the bullies like yourself to fuck off.