[Typo3] how to reference pages stored in General Storage SysFolder?

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I created a page (Type: Form, uid=475) in the SysFolder. 
http://.../index.php?id=475 returns:

Error!  The requested page does not exist!

Then I created another page (Type: Text, uid=476) in the same SysFolder. 
  http://.../index.php?id=476 returns a different page.

Web->List the General Storage folder returns the pages fine.

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