Hayhurum was a relatively small group Armeno-Greeks in Ottoman Armenian or better said Armenian speaking members of the Greek Orthodox church. The name comes from Hay meaning Armenian, hu meaning and, and Rûm meaning Greeks living in Turkey. The script they were using was Armenian, but written in Greek language.
In 1923, Hayhurum were forced out of Turkey and settled in Greece.
All the Hayhurum material is exceedingly rare and usually of ephemeral nature with a low surviving rate. This overlooked and almost forgotten group and its literature still awaits better researches.
We could trace two institutional examples (National Library of Armenia, University of Michigan).