Citigroup and American Express Co. are already global. Chase Manhattan Corp. issues cards in Hong Kong-where English is commonly spoken-and anticipates entering other markets. A study released this week by PSI Global found that demand for credit cards is growing throughout Europe. High demand for revolving credit is evident in Denmark, Finland, Germany, Italy, and Spain, the study found. Consumers in the emerging markets of Czech Republic, Hungary, Poland, and Turkey were seen as eager for new offerings. Europeans are ready for new competition in the credit card industry and "many are open to accepting cards from non-traditional players," according to Mark Sievewright, president of PSI Global, a market research firm based in Tampa. PSI Global interviewed 10,500 consumers in 13 European countries for the study.