He also studied the old Bulgar inscriptions and concluded that the Bulgar language was still spoken in the beginning of the 9th century.
Ivan Turgenev | Ivan Caryll | Ivan Lendl | Ivan Vazov | Ivan the Terrible | Ivan Shapovalov | Iván Rodríguez | Ivan Reitman | Ivan Pavlov | Ivan Lins | Hurricane Ivan | Ivan Krylov | Ivan Franko | Ivan Tors | Ivan Basso | Ivan Vladislavic | Ivan Neville | Ivan Meštrović | Ivan Varichev | Ivan Sergei | Ivan Panfilov | Ivan Kostov | Ivan Galamian | Iván Campo | Ivan Stang | Ivan's Childhood | Ivan Rybkin | Ivan Pregelj | Ivan Paskevich | Ivan Olbracht |
He spent the 22 years from 1976, when he took his doctor's degree (his dissertation was about the Celtic invasions in Thrace) under professor Ivan Venedikov, to his death in 1998, based in that country.