Suggestion: Many people say that hard copies of the book will help to focus on our studies. But my view on this thought is different, if you really wanted to learn a topic or a subject, then no one can distract you from learning it unless you distract yourself from it. I'm sure your mobile or any other electronic devices will not disturb you until you change your focus or thoughts to other things on the device. So, when you decide to learn something, just be focused on your studies. Some of us may get distracted by notification or anything else on the electronic devices. In those cases, you can find out your thoughts are not in your control. So, I recommend you, to purchase the hard copy of this book from the publishers and learn from it.
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