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.

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### Volume 16, Issue 2

#### Publication Date: June 1972

Frontmatter

Strong embeddings into categories of algebras

A. Pultr and V. Trnková; 183-195

Sklar-Stieltjes integrals

J. B. Harkin; 196-202

Supremum norm estimates for partial derivatives of functions of several real variables

Jan Boman; 203-216

Regular modules and rings

David J. Fieldhouse; 217-221

Pasting diffeomorphisms of $\mathbf{R}^{n}$

F. Wesley Wilson; 222-233

Moore-postnikov systems for non-simple fibrations

C. A. Robinson; 234-242

A note on topological Pontrjagin classes and the Hirzebruch index formula

Peter J. Kahn; 243-256

Amenable groups and varieties of groups

Gordon Keller; 257-269

On the Rogers-Ramanujan identities and partial $q$-difference equations

George E. Andrews; 270-275

On doubly transitive permutation groups of degree $n \equiv 2$ mod $4$

Michael Aschbacher; 276-279

Homology and semi-functors

F. W. Bauer; 280-293

On integrability and summability in vector spaces

D. R. Lewis; 294-307

On relators and diagrams for groups with one defining relation

C. M. Weinbaum; 308-322

The reduced symmetric product of projective spaces and the generalized Whitney theorem

S. Feder; 323-329

The automorphisms of certain subgroups of $PGL_{n}(V)$

Robert Solazzi; 330-348

On fours groups

J. L. Alperin; 349-351

Backmatter