Citation, obliteration, and plagiarism, as discussed in ancient Jewish sources

The preface to a 16th-century Hebrew book entitled Devek Tov, a supercommentary on the Pentateuch, includes an apology by the author for not citing all his sources. In his defense, he cites a passage in the Jerusalem Talmud that discusses the obliteration phenomenon. Following the trail of Jewish sayings on the importance of citation leads to a discussion of stealing ideas, i.e., plagiarism. Details of the search process, cataloging issues, incomplete indexes, and descriptions of complex locator systems found in Hebrew texts, concordances, and full-text databases are included. This detective work led to the discovery that Devek Tov was itself obliterated by incorporation into a later commentary on the Pentateuch.