What sets Drago’s work apart from other spectroscopy texts is its stubborn refusal to rely on "hand-waving" explanations. Many textbooks provide correlation tables for interpreting data; Drago provides the mathematical and physical derivations that create those tables.
One of the few classic texts that explains this niche but vital technique for iron and tin complexes with such precision. The Value of the "Drago Approach" What sets Drago’s work apart from other spectroscopy
EPR (ESR), Mossbauer, and NQR spectroscopy. and NQR spectroscopy.