TY - BOOK AU - Costinot, Arnaud AU - Werning Ivan AU - Clare Andres Rodriguez AU - National Bureau Of Economic Research TI - Micro to macro: Optimal trade policy with firm heterogeneity PY - 2016/// CY - Cambridge PB - NBER UR - http://elibrary.igidr.ac.in/e-library/working papers/NBER/2016/E16499.pdf ER -