Sankar, P. V., & Krishnamurthy, E. V. (1972). ALWIN - Algorithmic Chemical notation System for Organic Compounds. Part IV: Bridged Rings and Ring of Rings (Non-conventional Methods in Document Retrieval. 19). Journal of Information and Knowledge, 9(4), 575–584. https://doi.org/10.17821/srels/1972/v9i4/49268