Bjorn's Book Studio 3 CRX for Google Docs

Enables really large documents, divided into chapters. Use powerful features such as variables and stylesheets.
Combine sets of documents (chapters) into long books. Automatically merge these chapter documents into a final PDF (MSWord/Google Doc).
Apply a stylesheet to the final document, making sure that for example all headings look the same.
Quickly reuse content by using and managing your library of small snippet documents.
Convert footnotes in each chapter document to endnotes in the final book document.
Include text that frequently changes and appears often in your documents as variables.
Variables are also useful for providing information that is updated automatically, such as the current date or time.
They can also be useful when "single sourcing" - using the same source document to generate different versions of a document.
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