•Primary: original information; eg. correspondence, data, diaries, empirical studies, technical reports, dissertations and theses, works of art or literature.
In literary study, primary works are often novels, plays, poems, short stories, etc.
•Secondary: analyzes, comments on or provides criticism on primary information, eg. bibliographies, commentaries, monographs, review articles and editorials, scholarly journal articles, textbooks, works of criticism and interpretation.
This is where research is reported.
•Tertiary: interprets secondary information, eg. reference books, such as dictionaries, encyclopedias, and glossaries.
Use for background information.
•Reference sources: overview of topic eg. encyclopedias, in print or electronic.
•Books: analysis of topic, in depth background information.
•Journal articles: focus on specific subject.
•Grey literature: governments, organizations, think tanks – not publishers.
•Web pages: eg. government webpages such as gov.za.