Researchr is a web site for finding, collecting, sharing, and reviewing scientific publications, for researchers by researchers.
Sign up for an account to create a profile with publication list, tag and review your related work, and share bibliographies with your co-authors.
Ronald Vernon Book, Shimon Even, Sheila A. Greibach, Gene Ott. Ambiguity in Graphs and Expressions. IEEE Transactions on Computers, 20(2):149-153, 1971. [doi]
Abstract is missing.