https://gyanilabs.com/general-awareness/%e0%a4%b5%e0%a4%bf%e0%a4%ae%e0%a5%81%e0%a4%a6%e0%a5%8d%e0%a4%b0%e0%a5%80%e0%a4%95%e0%a4%b0%e0%a4%a3-demonetization-%e0%a4%94%e0%a4%b0-%e0%a4%a6%e0%a5%87%e0%a4%b6-%e0%a4%95%e0%a5%80-%e0%a4%86/