Aa gnationa vada kya sudhi book and title

the book is about caste system in hinduism .....how long this castesystem??


-- https://docs.google.com/viewer?a=v&pid=gmail&attid=0.2&thid=12a47c138e0163ab&mt=application%2Fpdf&url=https%3A%2F%2Fmail.google.com%2Fmail%2F%3Fui%3D2%26ik%3Da3b9842e40%26view%3Datt%26th%3D12a47c138e0163ab%26attid%3D0.2%26disp%3Dattd%26realattid%3Df_gc4rxgkg1%26zw&sig=AHIEtbREDJON6QDHYZ-cB3i9UpPZDogpJQ&pli=1