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 # Formula Cookbook
 
-A *formula* is a package definition written in Ruby. It can be created with `brew create <URL>` where `<URL>` is a zip or tarball, installed with `brew install <formula>`, and debugged with `brew install --drefebug --verbose <formula>`. Formulae use the [Formula API](https://www.rubydoc.info/github/Homebrew/brew/master/Formula) which provides various Homebrew-specific helpers.
+A *formula* is a package definition written in Ruby. It can be created with `brew create <URL>` where `<URL>` is a zip or tarball, installed with `brew install <formula>`, and debugged with `brew install --debug --verbose <formula>`. Formulae use the [Formula API](https://www.rubydoc.info/github/Homebrew/brew/master/Formula) which provides various Homebrew-specific helpers.
 
 ## Homebrew terminology