In scholarship, a secondary source is a document or recording that relates or discusses information originally presented elsewhere. Wikipedia

A written account of history based upon the evidence from primary sources Wikipedia Disambiguation

Document that discusses information originally presented elsewhere Wikidata

A study of past events or a past author written from the perspective of a later period of time; a document that draws on one or more historical primary sources and interprets or analyses them, including documents such as newspapers whose accuracy is open to question. Wiktionary

(historiography) document that draws on primary sources. Wiktionary (translation)