Transcription: Internal entities can save you a lot of time in typing, especially if you have text that's repetitive throughout your document. You can put it in an internal entity and have it expanded inside of your document and use that internal entity multiple times. The other thing is if that text ever changes, you only have to change it in one place. But there are a couple gotchas. The first one you ran into was having to double up your markup characters for the ampersand character and the less than character. There's another one that you really need to be aware of.
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