[1] J. Ježek: 
The lattice of equational theories. Part I: Modular elements. Czech. Math. J. 31 (1981), 127-153. 
MR 0604120 
[2] J. Ježek: 
The lattice of equational theories. Part II: The lattice of full sets of terms. Czech. Math. J. 31 (1981), 573-603. 
MR 0631604 
[4] J. Ježek: 
On atoms in lattices of primitive classes. Comment. Math. Univ. Carolinae 11 (1970), 515-532. 
MR 0269571 
[5] J. Ježek: 
Varieties of algebras with equationally definable zeros. Czechoslovak Math. J. 27 (1977), 473-503. 
MR 0453610 
[6] J. Ježek: 
EDZ-varieties: The Schreier property and epimorphisms onto. Comment. Math. Univ. Carolinae 17 (1976), 281-290. 
MR 0409317 
[7] M. Kozák: 
Finiteness conditions on EDZ-varieties. Comment. Math. Univ. Carolinae 17 (1976), 461-472. 
MR 0424646 
[9] A. Tarski: 
Equational logic and equational theories of algebras. 275 - 288 in: H. A. Schmidt, K. Schütte and H. J. Thiele, eds., Contributions to Mathematical Logic, North-Holland, Amsterdam 1968. 
MR 0237410 | 
Zbl 0209.01402