I WANT MY JOB IN CUSTOM DEPARTMENT, what book I have to read ?

I WANT MY JOB IN CUSTOM DEPARTMENT. So guide me and will get job advertisement, what book I have to read ?

There would be two typical routes. One would be through the Combined Graduate level examination by the Staff Selection Commission (www.ssc.nic.in), and the other, through the Civil Services examination of the Union Public Service Commission (www.upsc.gov.in).