A good monograph for basic identification of groups is the FAO Western Pacific Catalogue:
Carpenter, K. E. and V. H. Niem 1999. Species identification guide for fisheries purposes. The living marine resources of the western central Pacific. Batoid fishes, chimeras and bony fishes part 1 (Elopidae to Linophrynidae). FAO, Rome. v. 3: iii-vi + 1398-2068, I-IV.
For further literature, you may wish to consult the Catalog of Fishes online,