International law in general — Relation to municipal law — Bilateral agreements — Whether prevent enactment of general norms of municipal law and their application to foreign nationals not covered by such agreements — Primacy of treaty rules over municipal law for nationals of States covered by such agreements — The law of Switzerland

Treaties — Conclusion and operation of — Effect of municipal legislation — Double taxation agreements — Whether prevent enactment of general norms of municipal law on double taxation and their application to foreign nationals not covered by agreements — Primacy of treaty rules over municipal law for nationals of States covered by agreement — The law of Switzerland

Treaties — Conclusion and operation of — Effect of treaties on third parties — Double taxation agreements — Whether prevent enactment of norms of municipal law on double taxation and their application to foreign nationals not covered by agreement — Primacy of treaty rules over municipal law for nationals of States covered by bilateral agreements — The law of Switzerland