Scholary books ...
Look for book reviews using Library Search. If you find a book review in a scholarly journal, then it is probably a scholarly book. Read the review to verify this.
Search for books by the same author in Library Search. Has the author published other books that appear to be scholarly? Though not conclusive, this is a good sign.
Search for articles by this author to further examine his/her publishing history. Does this author publish in scholarly journals?
Go to the publisher's web site to see if it publishes other books that appear to be scholarly. How does the web site describe the author's book? Does it give you any clues about its academic / scholarly credibility? What kind of audience is the book targeting?
Perform a search in Google Scholar for the author's book. If it shows up in the results, look for the "Cited by" link to see if other publications have cited this work. Click on the link to browse the citing publications.
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