It appears that the first alphabet to be used for the language was the Greek alphabet[4] in the late 19th century. For example, orientalist Otto Blau claims that plays of Euripides had been translated into the Gagauz language and had been written with Greek letters.[5]
Beginning in 1957, Cyrillic was used up until the collapse of the Soviet Union in 1991. Gagauz currently uses a Latin-based alphabet, modelled after the modern Turkish alphabet, with the addition of three letters: ⟨ä⟩ to represent the sound of [æ] (as ⟨ə⟩ in Azeri; Turkish simply uses ⟨e⟩), ⟨ê⟩ to represent the sound of ə (as in Romanian ă) and ⟨ț⟩ or ⟨ţ⟩ to represent the sound [ts] (as in Romanian).
Ulutaş, İsmail. 2004. Relative clauses in Gagauz syntax. Istanbul: Isis Press. ISBN 975-428-283-8
Shabashov A.V., 2002, Odessa, Astroprint, "Gagauzes: terms of kinship system and origin of the people", (Шабашов А.В., "Гагаузы: система терминов родства и происхождение народа")