The homotopy axiom in semialgebraic cohomology. Hans Delfs — 1984 Journal für die reine und angewandte Mathematik
Semialgebraic Topology Over a Real Closed Field I: Paths and Components in the Set of Rational Points of an Algebraic Variety. Manfred Knebusch; Hans Delfs — 1981 Mathematische Zeitschrift
Semialgebraic Topology over a Real Closed Field II: Basic Theory of Semialgebraic Spaces. Manfred Knebusch; Hans Delfs — 1981 Mathematische Zeitschrift
On the homology of algebraic varieties over real closed fields. Manfred Knebusch; Hans Delfs — 1982 Journal für die reine und angewandte Mathematik