The Illinois Journal of Mathematics was founded in 1957 by R. Baer, J.L. Doob, A. Taub, G. Whitehead, and O. Zariski. The inaugural volume featured papers of many of the world's leading figures in the key areas of mathematics at the time. Since its inception, the IJM has published many influential papers, most notably the proof of the Four Color Conjecture by K. Appel and W. Haken. Distinguished researchers such as J. Bourgain, A. Calderon, S.S. Chern, H. Kesten, and K. Uhlenbeck have served as Editors of the IJM.

The last 5 years' volumes of the electronic version of the IJM is restricted to subscribers. For further information, please see the IJM Access Notice or contact the IJM office at ijm@math.uiuc.edu.

### Volume 44, Issue 1

#### Publication Date: Spring 2000

Frontmatter

Compact Lie groups acting on pseudomanifolds

Raimund Popper; 1-19

Reiter's condition $P_{2}$ and the Plancherel measure for hypergroups

Frank Filbir and Rupert Lasser; 20-32

The flow category of the action functional on $\mathcal{L}G_{N,N+K}(\mathbb{C})$

David E. Hurtubise; 33-50

On certain equivalent norms on Tsirelson's space

Edward W. Odell and Nicole Tomczak-Jaegermann; 51-71

Metrics of constant curvature 1 with three conical singularities on the $2$-sphere

Masaaki Umehara and Kotaro Yamada; 72-94

The Rankin-Selberg method on congruence subgroups

Shamita Dutta Gupta; 95-103

The complexity of the classification of Riemann surfaces and complex manifolds

G. Hjorth and A. S. Kechris; 104-137

Intrinsic ultracontractivity, conditional lifetimes and conditional gauge for symmetric stable processes on rough domains

Zhen-Qing Chen and Renming Song; 138-160

Elementary and integral-elementary functions

Miklós Laczkovich and Imre Z Ruzsa; 161-182

Spin(4) actions on $8$-dimensional manifolds (I)

Philippe Mazaud; 183-211

A full classification of contact metric $(k,\mu)$-spaces

E. Boeckx; 212-219

Backmatter