Wells, L. (1972). The product life cyle and nternational trade. Havard: President and Fellows of Havard College.
Παραπομπή Chicago StyleWells, Louis. The Product Life Cyle and Nternational Trade. Havard: President and Fellows of Havard College, 1972.
Παραπομπή MLAWells, Louis. The Product Life Cyle and Nternational Trade. Havard: President and Fellows of Havard College, 1972.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.