Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Mayank vedwal Vedwal
KM bangar is a good book for fast revision after u complete ur course. But there are several mistakes in this book so be careful while reading this book. U can use Textbook of geology by GB Mahapatra instead of bangar. GB Mahapatra will help u in bhu exam prepration too.