A Pāḷi grammar by Buddhappiya Thera (q.v.), also known as Dīpaṅkara.

It is based on Kaccāyana’s grammar, in its general outlines, and its full name is Padarūpasiddhi.

There is a Subcommentary (ṭīkā) on it ascribed to Buddhappiya himself. P.L.C., p.220 f.