1. Adams, M.E., Adaricheva, K.V., Dziobiak, W., Kravchenko, A.V.: Some open questions related to the problem of Birkhoff and Maltsev. Stud. Log. 78, 357–378 (2004)
2. Adams, M.E., Dziobiak, W.: $$Q$$-universal quasivarieties of algebras. Proc. Am. Math. Soc. 120, 1053–1059 (1994)
3. Adams, M.E., Dziobiak, W.: $$Q$$-universal varieties of bounded lattices. Algebra Univers. 48, 303–323 (2002)
4. Adams, M.E., Dziobiak, W., Sankappanavar, H.P.: Universality and $$Q$$-Universality in Varieties of Quasi-Stone Algebras. Algebras and Lattices in Hawaii, pp. 1–7. Lulu Press, Inc, Morrisville (2018)
5. Adams, M.E., Dziobiak, W., Sankappanavar, H.P.: A quasivariety: relatively finite-to-finite universal but not Q-universal. (to appear)