Forstner, H., & Ballance, R. (1990). Competing in a global economy: An empirical study on specialization and trade in manufactures. Unwin Hyman.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Forstner, Helmut, و Robert Ballance. Competing in a Global Economy: An Empirical Study on Specialization and Trade in Manufactures. London ; Boston: Unwin Hyman, 1990.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Forstner, Helmut, و Robert Ballance. Competing in a Global Economy: An Empirical Study on Specialization and Trade in Manufactures. Unwin Hyman, 1990.