1 Table of Contents: “... -- 10 The toy model for the virtual fundamental class and its localization -- 11 Degree 0 DT invariants...”

2 “.... Neumann introduced this system in the 1950s, and J. Moser popularized it as a toy model for celestial...”

3 “... sheet of paper; we see how M. C. Escher used geometric progressions in his art; and we learn how the toy...”

4 “... be flexed to display different pairs of faces, usually in cyclic order. Flexagons can be appreciated as toys...”