** A history of central sets**
(to appear in * Ergodic Theory and Dynamical Systems*)

** Notions of size in a semigroup -- an update from
a historical perspective** (to appear in * Semigroup Forum*)

(With D. Strauss)
**Some new results about the smallest ideal of beta S**
(to appear in * New York J. Math.*)

**The research of seven students at Howard University**
(to appear in * Contemporary Mathematics*)

(With W. Brian)
** Factoring a minimal ultrafilter into a thick part and
a syndetic part**

(With D. Strauss and L. Zamboni)
** Combining extensions of the Hales-Jewett Theorem
with Ramsey Theory in other structures**

(With K. Pleasant)
**Central Sets Theorem for arbitrary adequate partial semigroups**

(With D. Strauss)
**Some new results about the ubiquitous semigroup H**