To determine whether a book is a scholarly publication or not, you will need to make a judgment based on the following criteria:
Is the author or editor an academic or not? (thir academic affiliation, credentials, publications in scholarly journals)
Who is the the intended audience (academics or general readership)?
Is the publisher an academic press or research institute?
What is the level of discourse (language register) used in the publication?
Is the primary purpose of the book to disseminate research or to entertain?
Does the book and its chapter include references to other scholarly sources? Does the book and its chapters contain a bibliography or a list of used references?
Are graphics in the text placed there to support arguments or to entertain?
You can find answers to these questions by examining the book's title page, table and contents and bibliography at the end. In addition, skimming the introduction can help tremendously in terms of determining the intended audience and the overall purpose of the book.
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