 
 <prompt> Wetin be di time period wey dem mention second to last? Based on di previous question, write one context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: In di mid-19th century, Serbian (wey dey led by self-taught writer and folklorist Vuk Stefanović Karadžić) and most Croatian writers and linguists (wey dey represented by di Illyrian movement and led by Ljudevit Gaj and Đuro Daničić), propose di use of di most widespread dialect, Shtokavian, as di base for their common standard language. Karadžić standardised di Serbian Cyrillic alphabet, and Gaj and Daničić standardised di Croatian Latin alphabet, based on vernacular speech phonemes and di principle of phonological spelling. For 1850 Serbian and Croatian writers and linguists sign di Vienna Literary Agreement, wey declare their intention to create one unified standard. So one complex bi-variant language show face, wey di Serbs officially call "Serbo-Croatian" or "Serbian or Croatian" and di Croats "Croato-Serbian", or "Croatian or Serbian". But for practice, di variants of di common literary language serve as different literary variants, wey mainly dey different for word stock and stylistic devices. Di common phrase wey describe dis situation na say Serbo-Croatian or "Croatian or Serbian" na one language. During di Austro-Hungarian occupation of Bosnia and Herzegovina, di language of all three nations na "Bosnian" until di death of administrator von Kállay for 1907, wey dem come change di name to "Serbo-Croatian". 