Vimuttimagga (Pāli). ‘The Path to Liberation’, a treatise expounding the various aspects of the path to awakening (bodhi) as understood within the Theravāda tradition. The author of the work is Upatissa, who may have lived in the 3rd century ce. This work is generally thought to to have provided the inspiration for Buddhaghoṣa's later and more comprehensive compendium ‘The Path of Purification’ ( Visuddhimagga).

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)