Multiple Sources
Project Gutenberg encourages the use of multiple printed sources to create an eBook. For many historical works, including the US Declaration of Independence (the first Project Gutenberg eBook), there are variations among the printed sources. Another early example is the works of William Shakespeare. Project Gutenberg has several different versions of Shakespeare, including one based on the first edition folios. It has been typical, throughout the modern history of publishing, for different versions of a book to have variations.
In practice, the majority of Project Gutenberg eBooks rely on a single printed source. However, even those items might benefit from other sources — such as when some pages are missing, or illustrations come from a different version, or when typos/errata reports come from other sources.
It is a principal of Project Gutenberg that the eBooks in the collection are denoted as Project Gutenberg eBooks. Even if the publisher imprint and frontispiece from a printed work is included, there is no assurance that the content exactly matches that printed work. And, in fact, it will not match: minimally, the headers/footers will be removed, and paragraphs will flow together such that they span the pages of the printed source. Many other adjustments are typically made, as mentioned above.
For this reason, Project Gutenberg’s online catalog metadata does not include a citation to the source(s) used to create an eBook. Instead, Project Gutenberg should be cited as the publisher. For example, a bibliographic citation might have a form such as this:
Carroll, Lewis. “Alice’s Adventures in Wonderland.”. Urbana, Illinois: Project Gutenberg. Available: www.gutenberg.org/ebooks/11