This is not, as Mesquita appears to assume, simply a loose tag applied to a mixture of some proportion of Puranic sources as well as Madhva's own secret compositions, but is an independent dharmasastra treatise in its own name. It is quoted from by Sankara under Gaudapada-Karika 2.31, as well as by others in many other places. The editors of the Dharmakosa series out of Pune (vol. 1, 1937) state that they have tried to reconstruct this and other rare Smrtis from quotations found in various works. P.V. Kane31discusses this source also.
We have heard that the complete Vyasa-Smrti is part of a collection of Smrti texts published from Calcutta, but don't have an exact reference.