This document outlines criteria for a list of best-selling fiction authors, focusing on those with estimated sales exceeding 100 million copies worldwide. It acknowledges the difficulty in obtaining precise sales figures, relying instead on approximate numbers from reliable sources. The scope includes authors who have written or co-written fiction, with specific inclusion criteria for comic book creators whose works have been published in book formats such as tankōbon volumes or graphic novels. Authors whose sales figures are uncertain but potentially exceed the 100 million mark, like Ernest Hemingway and Victor Hugo, are mentioned as not being included due to a lack of exact data. The list's estimates are drawn from various years, making direct comparisons challenging.