Koa-á-chheh

Koa-á books (Hokkien: Koa-á-chheh; hàn-jī: 歌仔冊) is a form of vernacular literature of Hokkien language written in chinese characters, and it is popular in the Taiwanese and Chinese societies where Hoklo people live. Written Hokkien in hàn-jī system are deeply influenced by koa-á characters.

...
Wikipedia