Allen, v. c., & ravensburg, N. G. v. (1994). a beginner's business book. marburg consult for self-help promotion.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Allen, victor c., و Nicole Goler v. ravensburg. A Beginner's Business Book. marburg: marburg consult for self-help promotion, 1994.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Allen, victor c., و Nicole Goler v. ravensburg. A Beginner's Business Book. marburg consult for self-help promotion, 1994.