Evgenii Markov, Crimean Sketches: pictures of Crimean life, nature, and history (1884). Russian. Read it here.
Pavel Sumarokov, Travels through Crimea and Bessarabia in 1799. With historical and topographical descriptions (1800). Russian. Read it here.
Bibliotheca Chersonessitana (full runs of important 19th century journals in djvu format, including the Proceedings of the Odessa Society for History and Antiquities, and Bulletin of the Tavrida Scholarly Archival Commission)