Universal varieties of distributive double p-algebras
Vácłav Koubek, Jiří Sichler · Glasgow Mathematical Journal · 1985
An algebra (L; ν, ^, *, +, 0, 1) of type (2, 2, 1, 1, 0, 0) is a distributive double p-algebra provided (L; ν, ^, 0, 1) is a distributive (0, l)-lattice, and *, + are unary operations of pseudocomplementation, or dual pseudocomplementation, respectively: the operation * satisfies xa+ holds if and only if xνa = 1.