Optimum procedures for economic information retrieval. - H. S. Heaps; Larry H. Thiel (Inf. Storage Retr., 1970)

Criteria for Optimum Effectiveness of Information Retrieval Systems - H. S. Heaps (Inf. Control., 1971)

Program design for retrospective searches on large data bases. - Larry H. Thiel; H. S. Heaps (Inf. Storage Retr., 1972)

Selection of equifrequent word fragments for information retrieval. - Ernst J. Schuegraf; H. S. Heaps (Inf. Storage Retr., 1973)

A Theory of Relevance for Automatic Document Classification - H. S. Heaps (Inf. Control., 1973)

A comparison of algorithms for data base compression by use of fragments as language elements. - Ernst J. Schuegraf; H. S. Heaps (Inf. Storage Retr., 1974)

Data Compression of Large Document Data Bases. - H. S. Heaps (J. Chem. Inf. Comput. Sci., 1975)

Query processing in a retrospective document retrieval system that uses word fragments as language elements. - Ernst J. Schuegraf; H. S. Heaps (Inf. Process. Manag., 1976)

Compaction of Diagnostic Messages for Compilers. - H. S. Heaps; Thiruvengadam Radhakrishnan (Softw. Pract. Exp., 1977)