What is the hyperbolic plane? Can we crochet it?
What can you learn from your model?
Four strands in the history of geometry
Tidbits from the history of crochet
What is non-Euclidean geometry?
How to crochet a pseudosphere and a symmetric hyperbolic plane
Metamorphoses of the hyperbolic plane
Other surfaces with negative curvature : catenoid and helicoid
Who is interested in hyperbolic geometry now and how can it be used?