Comity — Trade — Antitrust — Price fixing — Vitamin C exports — United States antitrust law — Whether price fixing required by foreign government law — Determination of content of foreign law — Whether foreign government submissions on foreign law binding — Reciprocity — Treaties reflecting international practice

Economics, trade and finance — United States antitrust law — Price fixing — Vitamin C exports — Whether price fixing required by foreign government law — Determination of content of foreign law — Whether foreign government submissions on foreign law binding — Appropriate weight to be given to foreign government’s expressed view of own law

Relationship of international law and municipal law — Treaties — Treaties with formal mechanisms for one government to obtain from another official statement characterizing its laws — European Convention on Information on Foreign Law, 1968 — Inter-American Convention on Proof of and Information on Foreign Law, 1979 — United States not party to treaties — International practice — Whether consistent with understanding that government’s expressed view of own law entitled to substantial but not conclusive weight — The law of the United States