https://palathully.com/2018/07/%e0%b4%b7%e0%b4%be%e0%b4%a8%e0%b5%8b%e0%b5%bb-%e0%b4%b9%e0%b4%be%e0%b5%bc%e0%b4%9f%e0%b5%8d%e0%b4%9f%e0%b4%b2%e0%b4%bf-%e0%b4%a8%e0%b4%bf%e0%b4%af%e0%b4%ae%e0%b4%82-shannon-hartley-theorem/