1. On Angles Whose Squared Trigonometric Functions Are Rational

   • J. H. Conway
   • C. Radin
   • L. Sadun

   Pages: 321 - 332

2. Flipping Edges in Triangulations

   • F. Hurtado
   • M. Noy
   • J. Urrutia

   Pages: 333 - 346

3. On the Volume Formula for Hyperbolic Tetrahedra

   • Yunhi Cho
   • Hyuk Kim

   Pages: 347 - 366

4. Almost-Tiling the Plane by Ellipses

   • K. Kuperberg
   • W. Kuperberg
   • P. Valtr

   Pages: 367 - 375

5. Finding the Shortest Watchman Route in a Simple Polygon

   • S. Carlsson
   • H. Jonsson
   • B. J. Nilsson

   Pages: 377 - 402

6. On Grünbaum's Conjecture about Inner Illumination of Convex Bodies

   • V. Boltyanski
   • H. Martini
   • V. Soltan

   Pages: 403 - 410

7. Convexity and the Beta Invariant

   • C. Ahrens
   • G. Gordon
   • E. W. McMahon

   Pages: 411 - 424

8. A Construction of H ₄ without Miracles

   • J. R. Stembridge

   Pages: 425 - 427

9. Triangles in Euclidean Arrangements

   • S. Felsner
   • K. Kriegel

   Pages: 429 - 438

10. More Optimal Packings of Equal Circles in a Square

    • K. J. Nurmela
    • P. R. J. Ostergå rd

    Pages: 439 - 457

11. Coloring Quasicrystals with Prescribed Symmetries and Frequencies

    • A. El Kacimi Alaoui
    • R. Parthasarathy

    Pages: 459 - 475