What is "abecedar"

The Abecedar was a school book first published in Athens, Greece in 1925. The book became the subject of controversy with Bulgaria and Serbia when cited by Greece as proof it had fulfilled its international obligations towards its Slavic-speaking minority, because it had been printed in the Latin alphabet rather than the Cyrillic used by the Slavic languages of the southern Balkans. The book was initially published for the Slavic Macedonians in the Lerin dialect, and today it is published in Standard Macedonian, Standard Greek and Standard English.