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In general, categories should not be hidden. However, in the case of categories which are created solely for use with advanced coding functions like DPL or SMW, or when they have been created in order to facilitate the Game of Rassilon, it can be useful to hide them.
Please do not remove this message from this page without discussion at the Panopticon.
此分类为MediaWiki软件自动生成的“隐藏分类”。它包含使用内部魔术链接系统链接到ISBN的页面。