Sommaire

Concerning congruences on symmetric inverse semigroups
p. 1-9
On minimal sequences of type $l_+$ and bounded biorthogonal systems in Banach spaces
p. 11-14
Open and proper maps between convergence spaces
p. 15-23
Duality and algebraically irreducible semigroups
p. 24-29
Über die Kategorie der Menge stetiger Funktionen, welche Differentialgleichungen ohne Eindeutigkeit bestimmen
p. 30-33
On manifolds with connection
p. 34-44
Equicontinuous commutative semigroups of onto functions
p. 45-49
Meromorphisms of graphs
p. 50-56
Mittlere Darstellungen natürlicher Zahlen als Summe von $n$ $k$-ten Potenzen
p. 57-73
Vertices of space curves
p. 74-85
Curves of constant breadth
p. 86-94
Mixed problem for semilinear hyperbolic equation of second order with Dirichlet boundary condition
p. 95-122
On a theorem on the change of base point in a path connected space
p. 123-124
Center of a complete lattice
p. 125-138
Closed and open sets in topologies induced by lattice ordered vector groups
p. 139-150
The semigroup of fully indecomposable relations and Hall relations
p. 151-163
On $\sigma$-complete lattice ordered groups
p. 164-174
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