Where do scholars talk to other scholars in their discipline? In the field of English Language Literature, this conversation (the published version of it) usually takes place in scholarly journals and books. To get an article published in a scholarly journal, an author's manuscript must go through the peer review process. This involves having the manuscript read, critiqued, and approved by other scholars in the same field. Why should you care about peer review? You can assume some of the work of evaluating the quality of the information has been done for you if an article has been peer reviewed.
Here is a brief video from North Carolina State University Libraries explaining the peer review process:
You can visit the web site of the journal in which an article is published. Their information for authors will usually include a description of the submission process and say if they use peer review. Even easier, many of the MHC library's subscription databases (like MLA International Bibliography and Discover Supersearch) allow you to limit your search results to only peer reviewed items. Some other databases, like JStor and Project MUSE, contain articles and/or books only from scholarly publishers.
Visiting the publisher's web site and checking their information for authors is one way to determine if a book's publisher uses the peer review process. Most university presses (e.g., Harvard University Press, Oxford University Press, University of Toronto Press, etc.) use peer review, so a book from one of these publishers is a helpful indicator that the book is scholarly. Other things to check for are author credentials (is this an expert in the field), cited sources (footnotes and/or end notes), and intended audience (is the book intended for a scholarly or general audience). Unlike for articles, using the peer review limiter in the library's subscription databases to target scholarly books doesn't always work. The MLA International Bibliography peer review limiter only works for articles, while the Discover Supersearch peer review limiter only partially works for books.
Seminal works are highly original and influential works that have led to the further development or understanding of a subject. There is no one tool for discovering the most important works on a topic, but there are some ways to build your knowledge of the scholarly conversation surrounding a topic.
Use the library databases and catalog to search for articles and books on your topic. As you find articles and books on your topic, pay attention to their works cited lists and bibliographies. What articles and books are they citing? Notice in particular any works that are cited across the articles and books you've found. Repetition can be a sign that they're important.
Some databases include information about how many times an article or book has been cited by other sources. This is not a foolproof way of determining the relative importance of an article or book, however. No two databases include all of the same works, and it's possible an article or book has been cited many times because many people disagree with it. It's worth checking a few of the sources citing a work to see if that's the case or not.
A companion is a handbook or guide. You'll often find these for major authors, literary periods and genres. Companions usually contain collections of essays or entries on different aspects of the topic covered, often including bibliographies of additional sources to consult. Sometimes these are flagged as seminal or important. A critical or scholarly edition of a literary work often includes not just the primary text itself, but also a selection of critical essays on the author and work. To search for companions and critical editions, use these library catalogs:
Aside from seminal works, it's also important to include at least some newer scholarship in your research. The way we study literature changes over time: new schools of critical thought arise, levels of scholarly rigor vary, new techniques are found for studying literature, and new points of view are added to the conversation. We also continue to learn new things even about works that are hundreds of years old.
Most databases will allow you to limit your search to a specific date range. For example, the MLA International Bibliography's advanced search form's Search Options includes a Publication Date menu for this purpose. You can also use the Publication Date slider on the results page to target a specific date range after you've run your search.
Review articles summarize the current (as of the time of the article's writing) research on a topic. The author (or authors) offer their analysis of the research, too. Review articles can help you identify the scholars working on your topic, recent advances or discoveries, current debates, gaps in research, and also give you an idea of where the research might be headed next.