Ryan, R., & Lefberg, I. (1987). Persons of disability in Washington State: A statistical profile, 1970-1980. Labor Market and Economic Analysis Branch, Washington State Employment Security Dept..
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Ryan, Rosemary, و Irv Lefberg. Persons of Disability in Washington State: A Statistical Profile, 1970-1980. Olympia, Wash. (212 Maple Park, Olympia 98504-5311): Labor Market and Economic Analysis Branch, Washington State Employment Security Dept., 1987.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Ryan, Rosemary, و Irv Lefberg. Persons of Disability in Washington State: A Statistical Profile, 1970-1980. Labor Market and Economic Analysis Branch, Washington State Employment Security Dept., 1987.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.