Philosophiæ Naturalis Principia Mathematica
As for a sequence "nominative-genitive", it may be the norm in Latin in a similar ratio. E.g. "Systema Naturae"". Indeed, the sequence "nominative-genitive" must always be the norm in Peano's Interlingua, since the preposition "de" must introduce the genitive. Thus, "Philosophiæ Naturalis Principia Mathematica" would turn into "Principio Mathematico de Philosophia Naturale". Since the function of both the adjective and the genitive is often the same, one might infer that the sequence "noun-adjective" might always be the norm.