How to read these eBooks in ZIP format

I downloaded some eBooks in zip. The folder and structure are lik EPUB: META-INF, OEBPS folders and mimetype file. I changed the extension from zip to epub and tried to open them with all the EPUB readers I have (Adobe Digital Editions, Firefox plugin). None recognizes it. I can extract the content and read the HTML files but it’s less intuitive and there is no navigation between pages.
How can I read them?
Here is one example:
http://depositfiles.com/files/gmy45j6rq
~lionden~
Answer #1
If you just open the zip file with winzip or 7zip, you’ll get a pdf and an epub version of the book.
Extract.(unzip) the file to your desktop to make it easy to find.
No need to change anything.
View the pdf in Adobe or the epub in firefox or a reader like Calibre.
Answer #2
Use WinRar or 7Zip to unpack this file. Next read *.pdf file with Adobe Reader
Answer #3
I know some include multiple formats, but some only has folders like I described. These are the type that I can’t read without using the extracted HTML. a lot of the books you download from gfxworld dot ws are like that!
Answer #4
You got to unzip the files first. Then use Calibre E-book viewer to view them.