The Pomak language is taught at primary school level (using the Greek alphabet) in the Pomak regions of Greece, which are primarily in the Rhodope Mountains. The Pomaks of Thrace were, together with Turks and Roma, exempted from the population exchanges provided by the Lausanne Treaty (1923). The treaty made no mention of their language, but declared that their languages of education should be Turkish and Greek. The main school manual used for the teaching the language is 'Pomaktsou' by Moimin Aidin and Omer Hamdi, Komotini 1997. There is also a Pomak-Greek dictionary by Ritvan Karahodja, 1996. The Pomak dialects are on the Eastern side of the Yat isogloss of Bulgarian, yet many pockets of western Bulgarian speakers remain. A large number of them no longer transmit it; they have adopted Turkish as a first language and Greek as a second language. Recently the Community of the Pomaks of Xanthi, has announced its request to be treated equally and therefore to have the right of education in Greek schools without the obligation of learning the Turkish language.