International law in general — Nature and binding force — General rules of international law — Derogation from such rules by bilateral treaty — Right of establishment of aliens — The law of the Federal Republic of Germany

Treaties — Conclusion and operation — Operation and enforcement — Necessity for municipal legislation — Right of establishment of aliens — Discretionary powers of municipal authorities — Whether limited by international treaty obligations — Federal Republic of Germany-Greece Treaty of Navigation and Establishment, 1960 — Whether directly applicable under municipal law — The law of the Federal Republic of Germany

Treaties — Interpretation of — Agencies of interpretation — Interpretation by reference to memorandum to treaty — Federal Republic of Germany-Greece Treaty of Navigation and Establishment, 1960 — The law of the Federal Republic of Germany

The individual in international law — Aliens — Admission of — Right of establishment — Residence permit granted to foreign national — Prohibition on establishing trade or business — Discretionary powers of municipal authorities — Whether limited by international treaty obligations — Whether such obligations directly applicable under municipal law — Federal Republic of Germany-Greece Treaty of Navigation and Establishment, 1960 — Interpretation by reference to memorandum to Treaty — Whether any duty under international law to allow aliens access to business activity — Derogations from general international law by treaty — Clause of benevolence — The law of the Federal Republic of Germany