However, in his Dictionary of Turkish loanwords, Abdulah Škaljić maintains that the ''evo'' ending is more likely to have come from the widespread Slavic suffix  used to indicate place names, than from the Turkish ending . The first mention of the name Sarajevo was in a 1507 letter written by Firuz Bey. The official name during the 400 years of Ottoman rule was ''Saraybosna'' ("Palace of Bosnia"), which remains the city's name in Modern Turkish.