Christian cities of Alexandria, Antioch and Ephesus (see also Early Christian music). In his lexicographical discussion of instruments, the Persian geographer Ibn Khurradadhbih (d. 911) cited the lūrā (bowed lyra) as a typical instrument of the Byzantines along with the urghun (organ), shilyani (probably a type of harp or lyre), and the salandj (probably a bagpipe). Other instruments used in the folk Byzantine-era music, were kanonaki, oud, laouto, santouri and other instruments that are still played in post-Byzantine regions today. Ottoman era The Greeks were familiar, in this period that stretched from the 15th century to the time of Greek war of independence, with the traditional Greek folk music, elements of the Ottoman music, such as with surviving Byzantine music and more specifically, hymns: Church music. These genres have certainly reached a high degree of evolution. They were forms of a mono music that had many elements of ancient Greek origin but also, they had nothing to do with Western polyphonic music. By the beginning of the 20th century, music-cafés (καφέ-σαντάν) were popular in cities like Constantinople and Smyrna, where small groups of musicians from Greece played. The bands were typically led by a female vocalist and included a violin. The improvised songs typically exclaimed amán amán, which led to the name amanédhes (αμανέδες amanédes, singular αμανές amanés) or café-aman (καφέ-αμάν). Greek musicians of this period included Marika Papagika, Rosa Eskenazi and Rita Abatzi. This period also brought in the Rebetiko movement, which had local Smyrniote, Ottoman and Byzantine influences. Folk music (dimotiká or demotic) Greek folk music traditions are said to derive from the music played by ancient Greeks. There are said to be two musical movements in Greek folk music (παραδοσιακή μουσική): Acritic songs and Klephtic songs. Akritic music comes from the 9th century akrites, or border guards of the Byzantine Empire. Following the end of the Byzantine period, klephtic music arose before the Greek Revolution, developed among the kleftes, warriors who fought against the Ottoman Empire. Klephtic music is monophonic and uses no harmonic accompaniment. Dimotika tragoudia are only from the mainland and accompanied by clarinets, tambourines, laouto, violins and lyras, and include dance music like syrtó, kalamatianó, tsámiko and hasaposérviko, as well as vocal music like kléftiko. The lyrics are based on dimotiki (folk) poetry (usually by anonymous lyricist) and popular themes are love, marriage, humor, death, nature, water, sea, religious, about klephts, armatoloi, various war