Be careful, internally people are turning their backs against Bulgakov and to some extent, Gogol. Many think they are imperialistic sell-outs. Personally, some of the Soviet era Ukrainian writers such as Oles Honchar and Valerian Pidmohylnyi are also quite good. Honchar survived but Valerian and several others are known as the "Executed Renaissance" that was rising but all were taken during the Great Terror and executed at Solovki Camp. The University of Toronto has a free electronic library with English translations of many Ukrainian writers. So far, my favorite is Zakhar Berkut by Ivan Franko. It really captures the spirit and resilience of the Ukrainian people.