An Axiomatization of the Rational Data Objects. - Jan A. Bergstra; Alexander Ollongren; Theo P. van der Weide (FCT, 1977)

On Multilevel-Graph Grammars. - Alexander Ollongren (Graph-Grammars and Their Application to Computer Science and Biology, 1978)

Abstract Objects as Abstract Data Types. - H. Gerstmann; Alexander Ollongren (Abstract Software Specifications, 1979)

Axioms for multilevel objects. - A. Bergstra; H. J. M. Goeman; Alexander Ollongren; G. A. Terpstra; Theo P. van der Weide (Fundam. Informaticae, 1980)

Classroom experience with interactive formula manipulation. - Alexander Ollongren (ACM Commun. Comput. Algebra, 1985)

On a Particular Restricted Five-Body Problem An Analysis with Computer Algebra. - Alexander Ollongren (J. Symb. Comput., 1988)

A curious grammar. - Alexander Ollongren (Bull. EATCS, 1989)