Partial monounary algebras with common congruence relations
Partitions and congruences in algebras. I. Basic properties
Partitions and congruences in algebras. II. Modular and distributive equalities, complements
Partitions and congruences in algebras. III. Commutativity of congruences
Partitions and congruences in algebras. IV. Associable systems
Permutability, Distributivity of Equivalence Relations and Direct Products
Permutable tolerances
Perspektive Involutionen in der Geometrie der quadratischen Polynome.
Polythéorie de Galois abstraite dans le cas infini général
Präprimale Algebren, die arithmetische Varietäten erzeugen
Prime ideals in universal algebras
Products of mode varieties and algebras of subalgebras
Propriétés catégorielles dans la théorie des algèbres universelles