Using XML Schema inline?

I've been asked to make a current XML-document using an inline DTD into
a XML-document using inline XML Schema, instead of the DTD. The Schema
has to be inline, because it has to be one file only.

I've googled for inline XML schema definitions, because I am not sure
how I would implement it.

So, my question is, is it possible, and if yes, can you point me to an
example?

Thanks,

Jonas

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|   Jonas @ 55.75, 12.42   |

 "I went mad for a while,' said Ford, 'did me no end of good."