Head, Keith <br/><br/>
Increasing returns versus national product differentiation as an explanation for the pattern of U.S.-Canada trade /  
by Keith Head and John Ries. 
<br/><br/> Notas al pie del texto. 
<br/><br/>Bibliografía: p. 875-876. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Comercio internacional--Canadá<br/>Comercio intraindustrial--Canadá<br/>Comercio internacional--Estados Unidos<br/>Comercio intraindustrial--Estados Unidos