For public domain text not available online, you could use academic referencing style e.g Harvard style "Jess (2021) My Public licence poems"
Màkà èdèrèdè ǹgàlàbà ọ̀hà ná-ádị́ghị́ n'ị́ntānētị̀, ị́ nwèrè íké íjì ụ̀dị́ ńtụ̀áká àgụ́mákwụkwọ́ dị́kà ụ̀dị́ Harvard "Jess (2021) Ùrí íkíké ọ̀hàńezè m̀"