Deltoid curve - Wikipedia
MacTutor: Biographical History of Math – Occupy Math
Aiding the Teaching of Geometry and Affording Mathematical Recreation: Paper Folding in the Spirit of Sundara Rao of Madras
Watt's curve - Wikipedia
Envelopes and Offsets of Two Algebraic Plane Curves: Exploration of Their Similarities and Differences
Eight Curve -- from Wolfram MathWorld
Euler characteristic, Polyhedra, Topology, Geometry
Frozen Figure Eight
A History of Mathematics in South Africa: Modern Milestones
Graph Labelings: A Prime Area to Explore
Envelopes and Offsets of Two Algebraic Plane Curves: Exploration of Their Similarities and Differences
Trifolium -- from Wolfram MathWorld
Rose (mathematics) - Wikipedia
The Educational Times Database: History of the Educational Times and Mathematical Questions, 1847–1918
