If you have got any sort of p.d.f reader already installed , then click on the links . P.d.f file will open . Then at the top right most corner , there will be a arrow type option . That button is for downloading . . Or you can simply click right button of your mouse on the book's name, and then click on "save link as" , in this way too , it will be saved in both html and pdf formats .

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''Sufficient for us is Allah , and He is the best Disposer of affairs" Al-Quran