Selection of Sources:
A good approach to literature search is looking up a bibliography, an encyclopaedia or a review publication. This provides background information as also some useful references. After this preliminary search is over, searches should be carried out with secondary publications like abstracting and indexing services. Depending upon the topic, any one of the following situations may arise
i) Secondary periodicals are available on the subject.
ii) Secondary periodicals are available on the subject as well as on the broader area encompassing it.
iii) No secondary periodical is available on the subject, but available on the broader area.
iv) No secondary periodical is available on the subject, or on the broader subject.