Noun, Noun which may take the genitive case particle 'no'
1. materials; data; document
Wikipedia definition
2. Primary sourcePrimary sources are original materials. Generally, primary sources are not accounts written after the fact with the benefit of hindsight. Information for which the writer has no personal knowledge is not primary, although it may be used by historians in the abscence of a primary source.
Read “Primary source” on English Wikipedia
Read “資料” on Japanese Wikipedia
Read “Primary source” on DBpedia


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