APA (7th ed.) Citation

Dafydd ap Gwilym, a. 1. c., Helestine, N., & O'Connor, F. Selected poems. [publisher not identified].

Chicago Style (17th ed.) Citation

Dafydd ap Gwilym, active 14th century, Nigel Helestine, and Frank O'Connor. Selected Poems. Dublin, Cuala Press, 1944: [publisher not identified].

MLA (9th ed.) Citation

Dafydd ap Gwilym, active 14th century, et al. Selected Poems. [publisher not identified].