Law - Munish Bhandari
DTL - Bangar
IDTL-Bangar
ISCA - Dinesh Madam
Audit - Surbhi Bansal
Rest no idear
But Still suggest you dont look much for reference books .. study deeply and perfecly modules,practice manuals,rtps,suggested etc. The material provided by institute are the best to score good marks in compare to any of the reference books..