In order to reflect the files in a comment, I believe you would have to copy text and then paste it into a word document on your own computer. That text can be copied and pasted to a comment, I do it on occasion with quotes I’ve saved. A full article would have to be archived in a public domain in order to be source or excerpted.
You should be able to highlight the article in Adobe Reader, copy the text to the clipboard, and then paste it to FR.
(I just tested the hypothesis, and it works)
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You should first export the PDF file to Word format, then Copy & Paste the content into a text object in Photoshop. Then export the PSD file as HTML with the image sliced and the text object labeled a No Image area. Then open the HTML file in Dreamweaver and select File > Print Code. Take the printout and transcribe the text into the FreeRepublic Post Your Reply text area.
Simple.