Não informado. (2022). Progress Report. Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Não informado. Progress Report. Harrisburg, Pa: Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey, 2022.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Não informado. Progress Report. Commonwealth of Pennsylvania, Department of Internal Affairs, Bureau of Topographic and Geologic Survey, 2022.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.