Another angle: the user might be referring to a book that doesn't exist, which could be a problem. If I can't find information on Josip Boljkovac's "Knjiga," the paper might be challenging. In that case, I could suggest alternative approaches, like discussing a fictional analysis or focusing on Croatian literature in general.
The most reliable source for rare Eastern European PDFs is academic sharing networks. Josip Boljkovac Knjiga Pdf