H. P. Edmundson:
Language and information : Y. Bar-Hillel. Jerusalem Academic Press Ltd. and Addison-Wessley Publishing Co., Reading, Massachusetts, 1964.
27-29 Electronic Edition (link) BibTeX
Dagobert Soergel:
Mathematical analysis of documentation systems : An attempt to a theory of classification and search request formulation.
129-173 Electronic Edition (link) BibTeX
H. P. Edmundson:
The mathematical theory of context-free languages : S. Ginsburg. McGraw-Hill, New York, 1966. pp. ix + 232.
175 Electronic Edition (link) BibTeX
H. P. Edmundson:
The advanced theory of language as choice and chance : G. Herdan. Springer-Verlag, New York, 1966. pp. xiii + 459.
175-176 Electronic Edition (link) BibTeX