1971-1972/73/3

On the axiom of choice for families of finite sets

Some properties of convex metric spaces

Coreflective subcategories in general topology

Svenonius sentences and Lindström's theory on preservation theorems

Algebraic equivalence of ordinal numbers

Some properties of real functions of two variables and some consequences

Countable paracompactness of inverse limits and products

On some problems of Borsuk