Omarahdid what is a true pdf and how can I know it's a true pdf ?
Good question. I'd start [Login to see the link], but other indicators are correct page numbers, and a PDF file that has correct formatting and layout. This can be difficult to determine.
If you are not sure, or if you didn't get the file directly from the publisher, I would avoid posting it, unless you got it from a reputable source who has indicated that it is a "True PDF".