Following the citation trail

Once you have one good paper, it leads you to many more. This is often faster than keyword search.

Backward: what did this paper cite?

Read the reference list. Look for papers that are cited in the introduction and related work, or cited several times. These are the foundations of the topic.

Forward: who cited this paper later?

In Google Scholar or Semantic Scholar, click "Cited by". This shows newer papers that built on it, criticised it, or improved on it. Forward search is how you find out whether a result still holds.

Start with a survey

A survey (or review) paper sums up a whole area. Search for your topic plus "survey" or "review". A recent survey gives you the main ideas, the key papers, and often a list of open problems: a good source of research questions.

When to stop

You have read enough of the background when new papers keep citing papers you already know, and you stop finding new main ideas. This is sometimes called saturation. It does not mean you have read everything, which is impossible. It means you know the landscape.

Stay up to date

• Set up Google Scholar alerts for your keywords or for key authors.
• Follow the arXiv listings for your subject area.
• Read the accepted-paper lists of the main conferences in your field each year.

RememberThe best papers to read first are usually a recent survey, the two or three most-cited papers it names, and the newest papers that cite those.