Effect of taxonomy class and spanning set on identifying and counting rings in a compound

( 6 ) “The First 75 Years of Chemical Abstracts Service”. CAS Rep. 1982, 12, 3-9. (7) Perry, J. W. “The ACS Punched Card Committee-An Interim Report”. Chem. Eng. News 1949, 27 (1 l) , 754-756. (8) Baker, D. B. ”CAS Economics and Pricing”. “Proceedings of the Symposium on Chemical Abstracts in Transition”, Chicago, IL, Aug 28, 1973; Chemical Abstracts Service: Columbus, OH, 1974. Baker, D. B. “The Economics of Chemical Abstracts Service”. CAS Rep. 1974, 3, 3-7. (9) McCurdy, P. P. ‘Some Sausages, Some Skin”. Chem. Eng. News 1973, 51 (24), 1. (10) Rowlett, R. J., Jr. “Impact of the Computer System on CAS Editorial Processes and Publications and Services”. ‘Report on the 14th Chemical Abstracts Service Open Forum”, Chicago, IL, Sept !5,1970; Chemical Abstracts Service: Columbus, OH, 1971. (1 1) Weisgerber, D. W. ”Applications of Technology to CAS Data-Base Production”. InJ Serv. Use 1984, 4, 317-325. (12) Nelson, R. D.; Hensel, W. E.; Baron, D. N.; Beach, A. J. “Computer Editing of General Subject Heading Data for Chemical Abstracts Volume Indexes”. J . Chem. InJ Comput. Sei. 1975, 15, 85-94. (13) Soukup, K. M.; Hammond, S. E. “Author Name Processing at Chemical Abstracts Service: Name Matching Using Nonunique Bibliographic Identifiers”. J . Chem. InJ Comput. Sci. 1982, 22, 172-176. (14) Zamora, A. “Automatic Detection and Correction of Spelling Errors in a Large Data Base”. J . Am. SOC. Znf. Sci. 1980, 31, 51-57. (15) Gehring, S.; Rowlett, R. J., Jr.; Wigington, R. L.; Wood, J. L. ”Automated Editing”. CAS Rep. 1972, I , 3-10. (16) Farmer, N . A.; Tate, F. A.; Watson, C. E.; Wilson, G. A. “Extension and Use of the CAS Chemical Registry System”. CAS Rep. 1973, 2,