On universal partly ordered sets and classes

Categorical algebra

Saunders MacLane · Bulletin of the American Mathematical Society · 1965 · 251 citations · Full text

On full embeddings of categories of algebras

Zdeněk Hedrlín, Aleš Pultr · Illinois Journal of Mathematics · 1966 · 120 citations · Full text

Natural Sciences, Mathematics, Representation Theory +1

How comprehensive is the category of semigroups?

Zdeněk Hedrlín, Joachim Lambek · Journal of Algebra · 1969 · 92 citations

Natural Sciences, Mathematics, Set Theory +7

A rigid relation exists on any set

Petr Vopěnka, Aleš Pultr, Zdeněk Hedrlín · Czech Digital Mathematics Library (Institute of Mathematics CAS) · 1965 · 87 citations · Full text

Natural Sciences, Mathematics, Set Theory +3

Subobjects, adequacy, completeness and categories of algebras

John Isbell · 1964 · 84 citations

Natural Sciences, Computer Science, Mathematics +10