00383nam a2200121Ia 450000500170000010000210001724500310003826000090006952001410007858300190021994200060023899900170024420260716043351.0  aHELPMAN, Elnanan  aStructure of foreign trade  c1999  aDescribes what is known about foreign trade and in what waus ou understanding has improved as a result of the last 20 years of research.  c3/7/00kM2LMGR  cA  c45779d45779