Towers, Perrin, Forster & Crosby, & Financial Executives Research Foundation. (1983). Pension book reserves in West Germany: Their application to other countries, their potential applicability to the United States. Financial Executives Research Foundation.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Towers, Perrin, Forster & Crosby, و Financial Executives Research Foundation. Pension Book Reserves in West Germany: Their Application to Other Countries, Their Potential Applicability to the United States. Morristown, N.J.: Financial Executives Research Foundation, 1983.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Towers, Perrin, Forster & Crosby, و Financial Executives Research Foundation. Pension Book Reserves in West Germany: Their Application to Other Countries, Their Potential Applicability to the United States. Financial Executives Research Foundation, 1983.