Joint Committee on Forest Conservation. (1937). Forest practice handbook: Presenting the rules of forest practice for the Douglas fir region (Rev.). Joint Committee on Forest Conservation.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Joint Committee on Forest Conservation. Forest Practice Handbook: Presenting the Rules of Forest Practice for the Douglas Fir Region. Rev. Seattle: Joint Committee on Forest Conservation, 1937.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Joint Committee on Forest Conservation. Forest Practice Handbook: Presenting the Rules of Forest Practice for the Douglas Fir Region. Rev. Joint Committee on Forest Conservation, 1937.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.