Washington (State). Forest Practices Board, Washington (State). Forest Practices Board. Spotted Owl Science Advisory Group, & Hanson, E. (1993). Spotted owl habitat in Washington: A report to the Washington Forest Practices Board. Washington Forest Practices Board?.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Washington (State). Forest Practices Board, Washington (State). Forest Practices Board. Spotted Owl Science Advisory Group, و Eric Hanson. Spotted Owl Habitat in Washington: A Report to the Washington Forest Practices Board. [Olympia, Wash.?: Washington Forest Practices Board?, 1993.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Washington (State). Forest Practices Board, et al. Spotted Owl Habitat in Washington: A Report to the Washington Forest Practices Board. Washington Forest Practices Board?, 1993.